I think it's meant to play with your expectations. Normally someone's take being posted is to show them being confidently stupid, otherwise it isn't as interesting and doesn't go viral.However, because we're primed to view it from that lens, we feel crazy to think we're doing the math correctly and getting the "wrong answer" from what we assume is the "confident dipshit".
I fell for it. It's crazy to think how heavily I've been trained to believe everything I see is wrong in the most embarrassing and laughable way possible. That's pretty depressing if you think about it.
Some people insist there's no "correct" order for the basic arithmetic operations. And worse, some people insist the correct order is parenthesis first, then left to right.
Hopefully you can see where their confusion might come from, though. PEMDAS is more P-E-MD-AS. If you have a bunch of unparenthesized addition and subtraction, left to right is correct. A lot of like, firstgrader math problems are just basic problems that are usually left to right (but should have some extras to highlight PEMDAS somewhere I'd hope).
So they're mostly telling you they only remember as much math as a small child that barely passed math exercizes.
True, but as with many things, something has to be the rule for processing it. For many teachers as I've heard, order of appearance is 'the rule' when commutative properties apply. ... at least until algebra demands simplification, but that's a different topic.
No, you completely misunderstood my point. My point is not to describe all valid interpretations of the commutative property, but the one most slow kids will hear.
OFC the actual rule is the order doesn't matter, but kids that don't pick up on the nuance of the commutative property will still remember, "order of appearance is fine".
Yes thank you! If you have a sum it is really great to order it in a way that makes it better to ad in your head and i think that lots of people do that without thinking about it.
X=2+3+1+6+2+4+7+5
X=2+3+5+4+6+7+1+2
X=5+5 + 10 +7+1+2
X=10 + 10 + 7+3
X=10 + 10 + 10
I did not flip any signs, merely reversed the order in which the operations are written out. If you read the right side from right to left, it has the same meaning as the left side from left to right.
Hell, the convention that the sign is on the left is also just a convention, as is the idea that the smallest digit is on the right (which should be a familiar issue to programmers, if you look up big endian vs little endian)
If that's your idea of reversing the order, then you're not talking about the same thing as SpaceCadet@feddit.nl. They're talking about the order of operations and the associativity/commutativity property. You're talking about the order of the symbols.
They do, it's grouping those operations to say that they have the same precedence. Without them it implies you always do addition before subtraction, for example.
They do, it’s grouping those operations to say that they have the same precedence
They don't. It's irrelevant that they have the same priority. MD and DM are both correct, and AS and SA are both correct. 2+3-1=4 is correct, -1+3+2=4 is correct.
Without them it implies you always do addition before subtraction, for example
And there's absolutely nothing wrong with doing that, for example. You still always get the correct answer 🙄
Uh, no. I don't think you've thought this through, or you're just using (AS) without realizing it. Conversations around operator precedence can cause real differences in how expressions are evaluated and if you think everyone else is just being pedantic or is confused then you might not underatand it yourself.
Take for example the expression 3-2+1.
With (AS), 3-2+1 = (3-2)+1 = 1+1 = 2. This is what you would expect, since we do generally agree to evaluate addition and subtraction with the same precedence left-to-right.
With SA, the evaluation is the same, and you get the same answer. No issue there for this expression.
But with AS, 3-2+1 = 3-(2+1) = 3-3 = 0. So evaluating addition with higher precedence rather than equal precedence yields a different answer.
=====
Some other pedantic notes you may find interesting:
There is no "correct answer" to an expression without defining the order of operations on that expression. Addition, subtraction, etc. are mathematical necessities that must work the way they do. But PE(MD)(AS) is something we made up; there is no actual reason why that must be the operator precedence rule we use, and this is what causes issues with communicating about these things. People don't realize that writing mathematical expressions out using operator symbols and applying PE(MD)(AS) to evaluate that expression is a choice, an arbitrary decision we made, rather than something fundamental like most everything else they were taught in math class. See also Reverse Polish Notation.
Your second example, -1+3+2=4, actually opens up an interesting can of worms. Is negation a different operation than subtraction? You can define it that way. Some people do this, with a smaller, slightly higher subtraction sign before a number indicating negation. Formal definitions sometimes do this too, because operators typically have a set number of arguments, so subtraction is a-b and negation is -c. This avoids issues with expressions starting with a negative number being technically invalid for a two-argument definition of subtraction. Alternatively, you can also define -1 as a single symbol that indicates negative one, not as a negation operation followed by a positive one. These distinctions are for the most part pedantic formalities, but without them you could argue that -1+3+2 evaluated with addition having a higher precedence than subtraction is -(1+3+2) = -6. Defining negation as a separate operation with higher precedence than addition or subtraction, or just saying it's subtraction and all subtraction has higher prexedence than addition, or saying that -1 is a single symbol, all instead give you your expected answer of 4. Isn't that interesting?
Huh I just remembered the orders of arithmetic but parentheses trump all so do them first (I use them in even the calculator app). Mean I assume that's that that says but never learned that acronym is all. Now figuring out categories of words;really does my noodle in sometimes. Cause some words can be either depending on context. Math when it's written out has (mostly) the same answer. I say mostly because somewhere in the back of my brain there are some scenarios where something more complicated than straight arithmetic can come out oddly but written as such should come out the same.
I mean, arithmetic order is just convention, not a mathematical truth. But that convention works in the way we know, yes, because that's what's.. well.. convention
The rules are socially agreed upon. They are not a mathematical truth. There is nothing about the order of multiple different operators in the definition of the operators themselves. An operator is simply just a function or mapping, and you can order those however you like. All that matters is just what calculation it is that you're after
Just because a definition of an operator contains another operator, does not require that operator to take precedence. As you pointed out, 2+3*4 could just as well be calculated to 5*4 and thus 20. There's no mathematical contradiction there. Nothing broke. You just get a different answer. This is all perfectly in line with how maths work.
You can think of operators as functions, in that case, you could rewrite 2+3*4 as add(2, mult(3, 4)), for typical convention. But it could just as well be mult(add(2, 3), 4), where addition takes precedence. Or, similarly, for 2*3+4, as add(mult(2, 3), 4) for typical convention, or mult(2, add(3, 4)), where addition takes precedence. And I hope you see how, in here, everything seems to work just fine, it just depends on how you rearrange things. This sort of functional breakdown of operators is much closer to mathematical reality, and our operators is just convention, to make it easier to read.
Something in between would be requiring parentheses around every operator, to enforce order. Such as (2+(3*4)) or ((2+3)*4)
Isn't a Maths textbook, and has many mistakes in it
Just because a definition of an operator contains another operator, does not require that operator to take precedence
Yes it does 😂
2+3x4=2+3+3+3+3=14 by definition of Multiplication
2+3x4=5x4=20 Oops! WRONG ANSWER 😂
As you pointed out, 2+34 could just as well be calculated to 54 and thus 20
No, I pointed out that it can't be calculated like that, you get a wrong answer, and you get a wrong answer because 3x4=3+3+3+3 by definition
There’s no mathematical contradiction there
Just a wrong answer and a right one. If I have 1 2 litre bottle of milk, and 4 3 litre bottles of milk, even young kids know how to count up how many litres I have. Go ahead and ask them what the correct answer is 🙄
Nothing broke
You got a wrong answer when you broke the rules of Maths. Spoiler alert: I don't have 20 litres of milk
You just get a different answer
A provably wrong answer 😂
This is all perfectly in line with how maths work
2+3x4=20 is not in line with how Maths works. 2+3+3+3+3 does not equal 20 😂
add(2, mult(3, 4)), for typical
rule
But it could just as well be mult(add(2, 3), 4), where addition takes precedence
And it gives you a wrong answer 🙄 I still don't have 20 litres of milk
And I hope you see how, in here, everything seems to work just fine
No, I see quite clearly that I have 14 litres of milk, not 20 litres of milk. Even a young kid can count up and tell you that
it just depends on how you rearrange things
Correctly or not
our operators is just convention
The notation is, the rules aren't
Something in between would be requiring parentheses around every operator, to enforce order
No it wouldn't. You know we've only been using brackets in Maths for 300 years, right? Order of operations is much older than that
Such as (2+(3*4))
Which is exactly how they did it before we started using Brackets in Maths 😂 2+3x4=2+3+3+3+3=14, not complicated.
Social conventions are real, well defined things. Some mathematicians like to pretend they aren't, while using a truckload of them; that's a hypocritical opinion.
That's not to say you can't change them. But all of basic arithmetic is a social convention, you can redefine the numbers and operations any time you want too.
Yeah I know that. But I was feeling confused as to why it was here. That's why I was feeling trolled, because it made me doubt basic math for being posted in a memes community.
They did the joke wrong. To do it right you need to use the ÷ symbol. Because people never use that after they learn fractions, people treat things like a + b ÷ c + d as
a + b
-----
c + d
Or (a + b) ÷ (c + d) when they should be treating it as a + (b ÷ c) + d.
That's the most common one of these "troll math" tricks. Because notating as
a + b + d
-
c
Is much more common and useful. So people get used to grouping everything around the division operator as if they're in parentheses.
Now that's a good troll math thing because it gets really deep into the weeds of mathematical notation. There isn't one true order of operations that is objectively correct, and on top of that, that's hardly the way most people would write that. As in, if you wrote that by hand, you wouldn't use the / symbol. You'd either use ÷ or a proper fraction.
Personally, I'd call that 36 as written given the context you're saying it in, instead of calling it 1. But I'd say it's ambiguous and you should notate in a way to avoid ambiguities. Especially if you're in the camp of multiplication like a(b) being different from ab and/or a × b.
Please read this section of Wikipedia which talks about these topics better than I could. It shows that there is ambiguity in the order of operations and that for especially niche cases there is not a universally accepted order of operations when dealing with mixed division and multiplication. It addresses everything you've mentioned.
There is no universal convention for interpreting an expression containing both division denoted by '÷' and multiplication denoted by '×'. Proposed conventions include assigning the operations equal precedence and evaluating them from left to right, or equivalently treating division as multiplication by the reciprocal and then evaluating in any order;[10] evaluating all multiplications first followed by divisions from left to right; or eschewing such expressions and instead always disambiguating them by explicit parentheses.[11]
Beyond primary education, the symbol '÷' for division is seldom used, but is replaced by the use of algebraic fractions,[12] typically written vertically with the numerator stacked above the denominator – which makes grouping explicit and unambiguous – but sometimes written inline using the slash or solidus symbol '/'.[13]
Multiplication denoted by juxtaposition (also known as implied multiplication) creates a visual unit and is often given higher precedence than most other operations. In academic literature, when inline fractions are combined with implied multiplication without explicit parentheses, the multiplication is conventionally interpreted as having higher precedence than division, so that e.g. 1 / 2n is interpreted to mean 1 / (2 · n) rather than (1 / 2) · n.[2][10][14][15] For instance, the manuscript submission instructions for the Physical Review journals directly state that multiplication has precedence over division,[16] and this is also the convention observed in physics textbooks such as the Course of Theoretical Physics by Landau and Lifshitz[c] and mathematics textbooks such as Concrete Mathematics by Graham, Knuth, and Patashnik.[17] However, some authors recommend against expressions such as a / bc, preferring the explicit use of parenthesis a / (bc).[3]
More complicated cases are more ambiguous. For instance, the notation 1 / 2π(a + b) could plausibly mean either 1 / [2π · (a + b)] or [1 / (2π)] · (a + b).[18] Sometimes interpretation depends on context. The Physical Review submission instructions recommend against expressions of the form a / b / c; more explicit expressions (a / b) / c or a / (b / c) are unambiguous.[16]
6÷2(1+2) is interpreted as 6÷(2×(1+2)) by a fx-82MS (upper), and (6÷2)×(1+2) by a TI-83 Plus calculator (lower), respectively.
This ambiguity has been the subject of Internet memes such as "8 ÷ 2(2 + 2)", for which there are two conflicting interpretations: 8 ÷ [2 · (2 + 2)] = 1 and (8 ÷ 2) · (2 + 2) = 16.[15][19] Mathematics education researcher Hung-Hsi Wu points out that "one never gets a computation of this type in real life", and calls such contrived examples "a kind of Gotcha! parlor game designed to trap an unsuspecting person by phrasing it in terms of a set of unreasonably convoluted rules".[12]
Well, now you might be running into syntax issues instead of PEMDAS issues depending on what they're confused about. If it's 12 over 2*6, it's 1. If it's 12 ÷ 2 x 6, it's 36.
A lot of people try a bunch of funky stuff to represent fractions in text form (like mixing spaces and no spaces) when they should just be treating it like a programmer has to, and use parenthesis if it's a complex fraction in basic text form.
The P in PEMDAS means to solve everything within parentheses first; there is no "distribution" step or rule that says multiplying without a visible operator other than parentheses comes first. So yes, 36 is valid here. It's mostly because PEMDAS never shows up in the same context as this sort of multiplication or large fractions
Are you under the impression that atomizing your opponents statements and making a comment about each part individually without addressing the actual point (how those facts fit together) is a good debate tactic? Because it seems like all you've done is confuse yourself about what I was saying and make arguments that don't address it. Never mind that some of those micro-rebuttals aren't even correct.
Treat a + b/c + d as a + b/(c + d) I can almost understand, I was guilty of doing that in school with multiplication, but auto-parenthesising the first part is really crazy take, imo
Presuming PEMDAS is our order of operations and the 5 next to the parentheses indicates multiplication...
2+5(8-5) -> 2+5(3) -> 2+15=17
Other than adding a multiplication indicator next to the left parentheses for clarification (I believe it's * for programming and text chat purposes, a miniature "x" or dot for pen and paper/traditional calculators), this seems fine, yeah.
...I worry about how many people may not understand how to solve equations like these.
I don't think you're right. The wiki page literally uses a similar equation as an example of "elementary arithmetic." It also uses a similar one, but with variables, as an example in "elementary algebra." That implies that yes, this is arithmetic, and the introduction of variables is what makes it algebra.
It doesn't matter what course finally teaches it to you. That could be just out of convenience, not by definition part of that domain. It's been ages since I took it, though I could swear I learned this in pre-algebra (meaning before algebra), or earlier. I could be wrong on this though. Again, it's been a very long time.
You're very rude. Also, Ill informed, and you think you're smarter than you are. For example, this:
as an example in “elementary algebra.”
Algebra isn't taught until high school
Elementary doesn't mean elementary school. Do you think elementary particles are the ones they teach you in elementary school? Lol. Elementary means fundamental or basic.
I know. I was clowning on the dude mad about the arrows by offering one of numerous other meanings outside Boolean Algebra that sounded even more absurd in that context.
Some forms of programming syntax, although there are the fringe cases where an equation (or function in programming) is represented by a symbol in conjunction with a parentheses input.
For example:
y(x) = 2*x+3
5+y(1) = 10, as 1 is substituted in for x in the prior equation.
Not in most programming languages, though. You cannot start names with a number. Unless you're using some strange character that merely looks like a number, anyways. Programming with unicode can get weird but generally works without issue these days.
The way I was taught growing up, brackets are [these]. Parenthesis are (these).
Yes, technically the latter are also brackets. But they can also be called parenthesis, whereas the former is exclusively a bracket. So we were taught to call them separate words to differentiate while doing equations.
I'm a theoretical physics grad student and a night school maths teacher, I have never heard this distinction. People in academia around me call them round and square brackets.
It's a US vs UK (and probably others) distinction. The ( ) are almost never called brackets in the US, unless it's a regional thing I'm not aware of. Also the [ ] didn't get used in any math classes I was in the US up through calculus except for matrices.
They didn't say it's not defined, they said it's not a valid name. Most languages don't allow function names to start with a number, so 5 literally cannot be a function if that's the case.
But that's assuming this isn't some really obscure language.
I got some people really angry at me when I suggested writing some math expression with parenthesis so it would be clearer. I think someone told me that order of operations is like a natural law and not a convention, and thus everyone should know it or be able to figure it out.
I sometimes like to add unnecessary parentheses or brackets to section things off and improve legibility, but I don't do any math stuff collaboratively, so I have no idea whether others would find that disruptive or helpful.
Using parenthesis can really help if you want to simplify a term or need to rewrite something. I do that all the time because a lot of times you then can just cross stuff out fast on equations or get a common term that just has some factor instead of having a convolutet equation.
I got really angry because the prettier code formatter insists on removing parentheses, making things less clear. Because it's an "opinionated" formatter you can't tell it not to do that without using ugly hacks.
Sure, logically there are times when you don't need them. But, often it helps to explain what's happening in the code when you can use parentheses to group certain things. It helps in particular when you want to use "&&" and "||" to say "do X only if Y fails".
That's because it's already clear as is, as per the rules of Maths.
I think someone told me that order of operations is like a natural law
It's a natural consequence of the definitions of the operators. e.g. Multiplication is shorthand for repeated Addition - 2x3=2+2+2 - so if you don't do it before addition you end up with wrong answers. The order of operations rules is in fact just breaking everything down into Addition and Subtraction and then solving from there.
not a convention
There are some conventions, like left to right, but in that case that's only because students tend to make mistakes with signs when they don't go from left to right, so it's there to preserve teachers sanity.
That’s because it’s already clear as is, as per the rules of Maths.
More people evaluate 2+3x4 incorrectly than 2+(3x4). So, no, your answer does not hold up to my observed reality. You can throw as many "well technically" and "well actually" as you want, but that's not going to fix the bug or make a pr.
Division, Multiplication, Addition, and Subtraction
This is fucking so many people over... It should be limited - like Orders - to only Multiplication and Addition.
Because division is the same operation as multiplication, and subtraction is the same operation as addition, and they have the same "weight" in the order of operations (meaning, you do them left-to-right).
Because you don’t want people to know when to do Division and Subtraction? 😂
Because division is multiplication, and subtraction is addition.
No it isn’t, but they are both binary operators.
2/2 is the same as 2*½
2-2 is the same as 2+(-2)
And where are they going to do Division and Subtraction in the left to right if you’ve left them out? 🙄
Well, as I already said multiple times: Division = Multiplication and Subtraction = Addition, therefore they would be doing them together, left to right. As in: 9-3+2 would not confuse anyone who learned "Addition → Subtraction", as it does right now.
I learned BODMAS too! It seems BIDMAS is another one (British I think), PEMDAS is the weird American one, BEDMAS is a thing too. You're able to vary the first letter (parenthesis or brackets), second letter (indices/exponent/"order" or "operation"), and the order of multiplication/division (MS or SM) and addition/SUBTRACTION (AD or DA)
Technically roots are a form of exponent, just fractional (square root is power of 1/2, for instance). I can see how it could be easier to conceptualize when you break it down like that though. Neat to see the differences compared to the US breakdown :)
Okay then, but, fun story, the BODMAS they're talking about is also just PEMDAS using different words and a different listed order for multiplication/division, with the understanding that it's more properly PE(MD)(AS)
The order of operations is the important bit and everyone learns it that way. What causes the arguments is when dummies online forget that M+D or A+S can theoretically be done properly in any order and that part is a matter of preference.
I'll never understand these approaches to learning. They require remembering the phrase, and then require remembering how the phrase translates to the rules you need to remember.
I'll just remember the rules in the first place. Less effort.
There's just no way rote learning is easier than mnemonics unless you have a photographic memory.
Shit, I still remember the order of taxonomic ranks after seeing the phrase "King Phillip came over from Germany stoned" written in a used bio textbook 30 years ago when we never even made it to that chapter to officially study in class. I guarantee I never would've remembered the list "kingdom phylum class order family genus species".
I'm in my 40s, and have been playing music since single digits. I still remember the order of lines in the staffs with "Every Good Boy Deserves Fudge", "FACE", "Good Boys Deserve Fudge Always", and "All Cows Eat Grass". I did teach my kids "Good Burritos Don't Fall Apart", though, since they seem to like burritos.
My internal math nerd agrees with the grandparent though, for some reason I just remembered the order of operations and was confused when my kids came home with PEDMAS. But to be fair, I use the order of operations every day at work, so 🤷. I'm also one of those people who will insist on using parentheses everywhere there's more than two terms, though, so take from that what you will.
I’ll never understand these approaches to learning. They require remembering the phrase, and then require remembering how the phrase translates to the rules you need to remember
Yeah, exactly, but the U.S. seems to have a chip on it's shoulder about always doing everything differently to the whole rest of the world. "Maths? We're not going to use BEDMAS, and we're not going to call them Brackets, and...".
You don't necessarily have to do parentheses first. What matters is that the things inside the parentheses are a group that you can't break apart. If you have 10÷2+3-2*(2+1) you can do the division first 5+3-2*(2+1) then the addition outside the parentheses 8-2*(2+1) It's just that before you do the multiplication of the term outside the parentheses, you have to handle the parentheses group, so you get 8-2*3 -> 8-6 -> 2
Yeah, maybe. My Year 7 students, who have come fresh to me from Year 6, use BEDMAS, and I teach BEDMAS for consistency (I also think it's a better acronym anyway - think of a massive 4-poster bed to ingrain the idea of BED-MAS)...
Was anyone else ever taught it as BOMDAS as opposed to BODMAS?
I don't think so, and I've seen Maths textbooks from all over the world. Only the U.S. wants to reverse the order of DM from everyone else's acronym. 🙄
You're talking math, I'm talking programming languages. We are not the same.
Most languages throw a syntax error if the multiplication symbol is missing.
I don't get why these kind of post crop up so often.
The answer to them doesn't matter and these aren't really math questions, because there is no context given. This is just endless discussions about different people having different assumptions on notation used there...
In real math, where the numbers mean something, good and consistent notation is important, but not necessary, because the order of operations or what those operations are exactly would be clear through the context of these formulas. Good notation just makes it easier to spot errors, work with formulas or to avoid confusion.
Here is what I would assume this formula could mean. Someone has 2 apples and 5 bags of apples that initially came with 8 apples each inside, but someone else ate 5 apples from each of these bags.
With this context it is pretty clear what the answer would be.
Or it simply could be that I haven't needed to concern myself with the order of operations more than a dozen times since high school. Even when working as a web coder it was so seldom necessary that I can't recall a single example.
The US education system was still pretty decent when I was in middle and high school in the 1980s, so we definitely covered this in algebra.
That's so evil and subtle. It took me multiple attempts to figure it out. You have to have quite the sharp eye to realize: no, you do not stop at calculating the numbers in parantesis first. You don't add the resulting numbers, there is no +/- operator, so the number in parantesis is the power of the number before it. But wait! if You calculated 2+5 = 7 * 3 and hot 21, you are wrong. Remember that multiplication goes first, so it's: 2+5(8-5) = 2+5*3=2+15=17
But I also haven't done this kind of math since 4th grade so I'm not sure if the joke is that this is the real answer or the answer you get doing it wrong... 🤔
Seriously, every time this comes up and everyone makes a huge deal out of it, I keep thinking, "none of the people writing these better be teachers." You have to be more clear than this.
Edit: ok, not so much this one. I just read the words and assumed the math problem was one of the ambiguous ones. Stand down, soldiers.
They have the same rules, but they don't require Maths teachers to have a Maths qualification (in Australia you have to have a Masters), and they have been sliding in world rankings for more than a decade.
I live in Australia and don’t recall my school at all teaching me this in maths class
I'm in Australia, and I remember being taught it, and I teach it.
people exist that live in other countries and every countries education system is different
The rules are the same everywhere, only the notation varies (in Germany they use . for multiply and : for divide, and say "dot before slash", slash being - and +).
Why should anyone do that, an implied multiplication is the normal thing you learn in (I think?) somewhere between 5th to 7th grade. You only add an operator if it's something else. It's as basic as PEMDAS.
There's no such thing. It's a Term/Product. Google is a prime source of Maths disinformation (yes, they have been told it's wrong, repeatedly, so it's disinformation).
So you're the guy that asked chat GPT if you could enter Chile without a passport, said yes, come to Chile and had to go back because you actually needed a passport huh?.
It surprises me the amount of people who just "outsource" their intelligence to a fking chatbot and then proceed their way in life taking moronic decisions all over, a reminder AI companies depend on people being too lazy to think to be able to sell their products.
611 Comments
SSUPII@sopuli.xyz · 336 pts · 253d
I feel like I am getting trolled
Isn't 17 the actual right answer?
NewDark@lemmings.world · 168 pts · 253d
Exactly
sem@lemmy.blahaj.zone · 135 pts · 253d
So it's just an unfunny meme?
NewDark@lemmings.world · 103 pts · 253d
I think it's meant to play with your expectations. Normally someone's take being posted is to show them being confidently stupid, otherwise it isn't as interesting and doesn't go viral.However, because we're primed to view it from that lens, we feel crazy to think we're doing the math correctly and getting the "wrong answer" from what we assume is the "confident dipshit".
There's layers beyond the superficial.
namingthingsiseasy@programming.dev · 24 pts · 253d
I fell for it. It's crazy to think how heavily I've been trained to believe everything I see is wrong in the most embarrassing and laughable way possible. That's pretty depressing if you think about it.
ExtremeDullard@piefed.social · 21 pts · 253d
As most memes are.
Ghyste@sh.itjust.works · 10 pts · 253d
Not even a meme.
Klear@quokk.au · 1 pts · 234d
It's engagement bait.
0x0@lemmy.zip · 1 pts · 252d
More like a sad realization of the state of (un)education in some parts of the so-called civilized world.
You laugh not to cry.
marcos@lemmy.world · 40 pts · 253d
Some people insist there's no "correct" order for the basic arithmetic operations. And worse, some people insist the correct order is parenthesis first, then left to right.
Both of those sets of people are wrong.
MotoAsh@piefed.social · 10 pts · 253d
Hopefully you can see where their confusion might come from, though. PEMDAS is more P-E-MD-AS. If you have a bunch of unparenthesized addition and subtraction, left to right is correct. A lot of like, firstgrader math problems are just basic problems that are usually left to right (but should have some extras to highlight PEMDAS somewhere I'd hope).
So they're mostly telling you they only remember as much math as a small child that barely passed math exercizes.
SpaceCadet@feddit.nl · 10 pts · 253d
If you have a bunch of unparenthesized addition and subtraction, left to right doesn't matter.
1 + 2 + 3 = 3 + 2 + 1
MotoAsh@piefed.social · 4 pts · 253d
True, but as with many things, something has to be the rule for processing it. For many teachers as I've heard, order of appearance is 'the rule' when commutative properties apply. ... at least until algebra demands simplification, but that's a different topic.
SpaceCadet@feddit.nl · 5 pts · 253d
Well the rule is: any order goes. Summation is commutative.
MotoAsh@piefed.social · 4 pts · 252d
No, you completely misunderstood my point. My point is not to describe all valid interpretations of the commutative property, but the one most slow kids will hear.
OFC the actual rule is the order doesn't matter, but kids that don't pick up on the nuance of the commutative property will still remember, "order of appearance is fine".
Quatlicopatlix@feddit.org · 2 pts · 252d
Yes thank you! If you have a sum it is really great to order it in a way that makes it better to ad in your head and i think that lots of people do that without thinking about it. X=2+3+1+6+2+4+7+5 X=2+3+5+4+6+7+1+2 X=5+5 + 10 +7+1+2 X=10 + 10 + 7+3 X=10 + 10 + 10
SmartmanApps@programming.dev · 0 pts · 236d
That's because students often make mistakes with signs when they do it in a different order, so we tell them to stick to left to right
kuberoot@discuss.tchncs.de · -3 pts · 252d
Right, because 1-2-3=3-2-1.
howrar@lemmy.ca · 2 pts · 251d
You flipped the sign on the 3 and 1.
kuberoot@discuss.tchncs.de · 0 pts · 251d
I did not flip any signs, merely reversed the order in which the operations are written out. If you read the right side from right to left, it has the same meaning as the left side from left to right.
Hell, the convention that the sign is on the left is also just a convention, as is the idea that the smallest digit is on the right (which should be a familiar issue to programmers, if you look up big endian vs little endian)
howrar@lemmy.ca · 2 pts · 246d
If that's your idea of reversing the order, then you're not talking about the same thing as SpaceCadet@feddit.nl. They're talking about the order of operations and the associativity/commutativity property. You're talking about the order of the symbols.
SmartmanApps@programming.dev · -1 pts · 236d
Yes you did! 😂
No, merely reversing the order gives -3-2+1 - you changed the signs on the 1 and 3.
Starts with -3, which you changed to +3
when you don't change any of the signs it does 😂
Nope, it's a rule of Maths, Left Associativity.
SmartmanApps@programming.dev · 0 pts · 236d
No, 1-2-3=-3-2+1. You changed the signs on the 1 and the 3.
Feathercrown@lemmy.world · 5 pts · 253d
PE(MD)(AS)
Now just remember to account for those parentheses first...
SmartmanApps@programming.dev · -1 pts · 236d
Those Brackets don't matter. I don't know why people insist it does
Feathercrown@lemmy.world · 1 pts · 235d
They do, it's grouping those operations to say that they have the same precedence. Without them it implies you always do addition before subtraction, for example.
SmartmanApps@programming.dev · -2 pts · 235d
They don't. It's irrelevant that they have the same priority. MD and DM are both correct, and AS and SA are both correct. 2+3-1=4 is correct, -1+3+2=4 is correct.
And there's absolutely nothing wrong with doing that, for example. You still always get the correct answer 🙄
Feathercrown@lemmy.world · 2 pts · 235d
Uh, no. I don't think you've thought this through, or you're just using (AS) without realizing it. Conversations around operator precedence can cause real differences in how expressions are evaluated and if you think everyone else is just being pedantic or is confused then you might not underatand it yourself.
Take for example the expression 3-2+1.
With (AS), 3-2+1 = (3-2)+1 = 1+1 = 2. This is what you would expect, since we do generally agree to evaluate addition and subtraction with the same precedence left-to-right.
With SA, the evaluation is the same, and you get the same answer. No issue there for this expression.
But with AS, 3-2+1 = 3-(2+1) = 3-3 = 0. So evaluating addition with higher precedence rather than equal precedence yields a different answer.
=====
Some other pedantic notes you may find interesting:
There is no "correct answer" to an expression without defining the order of operations on that expression. Addition, subtraction, etc. are mathematical necessities that must work the way they do. But PE(MD)(AS) is something we made up; there is no actual reason why that must be the operator precedence rule we use, and this is what causes issues with communicating about these things. People don't realize that writing mathematical expressions out using operator symbols and applying PE(MD)(AS) to evaluate that expression is a choice, an arbitrary decision we made, rather than something fundamental like most everything else they were taught in math class. See also Reverse Polish Notation.
Your second example, -1+3+2=4, actually opens up an interesting can of worms. Is negation a different operation than subtraction? You can define it that way. Some people do this, with a smaller, slightly higher subtraction sign before a number indicating negation. Formal definitions sometimes do this too, because operators typically have a set number of arguments, so subtraction is a-b and negation is -c. This avoids issues with expressions starting with a negative number being technically invalid for a two-argument definition of subtraction. Alternatively, you can also define -1 as a single symbol that indicates negative one, not as a negation operation followed by a positive one. These distinctions are for the most part pedantic formalities, but without them you could argue that -1+3+2 evaluated with addition having a higher precedence than subtraction is -(1+3+2) = -6. Defining negation as a separate operation with higher precedence than addition or subtraction, or just saying it's subtraction and all subtraction has higher prexedence than addition, or saying that -1 is a single symbol, all instead give you your expected answer of 4. Isn't that interesting?
orbitz@lemmy.ca · 2 pts · 252d
Huh I just remembered the orders of arithmetic but parentheses trump all so do them first (I use them in even the calculator app). Mean I assume that's that that says but never learned that acronym is all. Now figuring out categories of words;really does my noodle in sometimes. Cause some words can be either depending on context. Math when it's written out has (mostly) the same answer. I say mostly because somewhere in the back of my brain there are some scenarios where something more complicated than straight arithmetic can come out oddly but written as such should come out the same.
SmartmanApps@programming.dev · 0 pts · 236d
You can do addition and subtraction in any order and it's still correct
SkyeStarfall@lemmy.blahaj.zone · 2 pts · 252d
I mean, arithmetic order is just convention, not a mathematical truth. But that convention works in the way we know, yes, because that's what's.. well.. convention
SmartmanApps@programming.dev · 0 pts · 236d
Nope, rules arising from the definition of the operators in the first place.
It most certainly is a mathematical truth!
The mnemonics are conventions, the rules are rules
SkyeStarfall@lemmy.blahaj.zone · 0 pts · 236d
The rules are socially agreed upon. They are not a mathematical truth. There is nothing about the order of multiple different operators in the definition of the operators themselves. An operator is simply just a function or mapping, and you can order those however you like. All that matters is just what calculation it is that you're after
SmartmanApps@programming.dev · 0 pts · 235d
Nope! Universal laws.
Yes they are! 😂
That's exactly where it is. 2x3 is defined as 2+2+2, therefore if you don't do Multiplication before Addition you get wrong answers
No you can't! 😂 2+3x4=5x4=20, Oops! WRONG ANSWER 😂
And if you want the right answer then you have to obey the order of operations rules
SkyeStarfall@lemmy.blahaj.zone · 0 pts · 235d
That's a very simplistic view of maths. It's convention https://en.wikipedia.org/wiki/Order_of_operations
Just because a definition of an operator contains another operator, does not require that operator to take precedence. As you pointed out, 2+3*4 could just as well be calculated to 5*4 and thus 20. There's no mathematical contradiction there. Nothing broke. You just get a different answer. This is all perfectly in line with how maths work.
You can think of operators as functions, in that case, you could rewrite 2+3*4 as add(2, mult(3, 4)), for typical convention. But it could just as well be mult(add(2, 3), 4), where addition takes precedence. Or, similarly, for 2*3+4, as add(mult(2, 3), 4) for typical convention, or mult(2, add(3, 4)), where addition takes precedence. And I hope you see how, in here, everything seems to work just fine, it just depends on how you rearrange things. This sort of functional breakdown of operators is much closer to mathematical reality, and our operators is just convention, to make it easier to read.
Something in between would be requiring parentheses around every operator, to enforce order. Such as (2+(3*4)) or ((2+3)*4)
SmartmanApps@programming.dev · -1 pts · 235d
The Distributive Law and Arithmetic is very simple.
Nope, a literal Law. See screenshot
Isn't a Maths textbook, and has many mistakes in it
Yes it does 😂
2+3x4=2+3+3+3+3=14 by definition of Multiplication
2+3x4=5x4=20 Oops! WRONG ANSWER 😂
No, I pointed out that it can't be calculated like that, you get a wrong answer, and you get a wrong answer because 3x4=3+3+3+3 by definition
Just a wrong answer and a right one. If I have 1 2 litre bottle of milk, and 4 3 litre bottles of milk, even young kids know how to count up how many litres I have. Go ahead and ask them what the correct answer is 🙄
You got a wrong answer when you broke the rules of Maths. Spoiler alert: I don't have 20 litres of milk
A provably wrong answer 😂
2+3x4=20 is not in line with how Maths works. 2+3+3+3+3 does not equal 20 😂
rule
And it gives you a wrong answer 🙄 I still don't have 20 litres of milk
No, I see quite clearly that I have 14 litres of milk, not 20 litres of milk. Even a young kid can count up and tell you that
Correctly or not
The notation is, the rules aren't
No it wouldn't. You know we've only been using brackets in Maths for 300 years, right? Order of operations is much older than that
Which is exactly how they did it before we started using Brackets in Maths 😂 2+3x4=2+3+3+3+3=14, not complicated.
marcos@lemmy.world · -1 pts · 252d
Social conventions are real, well defined things. Some mathematicians like to pretend they aren't, while using a truckload of them; that's a hypocritical opinion.
That's not to say you can't change them. But all of basic arithmetic is a social convention, you can redefine the numbers and operations any time you want too.
SmartmanApps@programming.dev · 0 pts · 236d
So are the laws of nature, that Maths arises from
No, you making false accusations against Mathematicians is a strawman
You can change the conventions, you cannot change the rules
Nope, law of nature. Even several animals know how to count.
And you end up back where you started, since you can't change the laws of nature
SmartmanApps@programming.dev · 0 pts · 236d
And those people are wrong
As per Maths textbooks
All Maths textbooks are wrong?? 😂
Petter1@discuss.tchncs.de · 0 pts · 248d
Well, this is just a writing standard that is globally agreed on,
The writing rules are defined by humans not by natural force
(That one thing and another thing are two things, is a rule from nature, as comparison)
SmartmanApps@programming.dev · -1 pts · 236d
No, it's a universal rule of Maths
Maths is for describing natural forces, and is subject to those laws
Yep, there are even some animals who understand that, and all of Maths is based upon it.
RizzRustbolt@lemmy.world · 11 pts · 253d
There is no answer. Because there is no question.
imetators@lemmy.dbzer0.com · 2 pts · 253d
That is a problem, tho
polydactyl@lemmy.world · 4 pts · 253d
I know the solution
SmartmanApps@programming.dev · 0 pts · 236d
So Maths test says "2+3 ____", and you write "that's not a question" on the blank line?? 😂
pixeltree@lemmy.blahaj.zone · 9 pts · 253d
SSUPII@sopuli.xyz · 24 pts · 253d
Yeah I know that. But I was feeling confused as to why it was here. That's why I was feeling trolled, because it made me doubt basic math for being posted in a memes community.
JackbyDev@programming.dev · 6 pts · 253d
They did the joke wrong. To do it right you need to use the ÷ symbol. Because people never use that after they learn fractions, people treat things like a + b ÷ c + d as
Or (a + b) ÷ (c + d) when they should be treating it as a + (b ÷ c) + d.
That's the most common one of these "troll math" tricks. Because notating as
Is much more common and useful. So people get used to grouping everything around the division operator as if they're in parentheses.
CannonFodder@lemmy.world · 4 pts · 253d
Or
12 / 2(6)
And trying to argue this is 36.
JackbyDev@programming.dev · 7 pts · 253d
Now that's a good troll math thing because it gets really deep into the weeds of mathematical notation. There isn't one true order of operations that is objectively correct, and on top of that, that's hardly the way most people would write that. As in, if you wrote that by hand, you wouldn't use the
/symbol. You'd either use ÷ or a proper fraction.It's a good candidate for nerd sniping.
Personally, I'd call that 36 as written given the context you're saying it in, instead of calling it 1. But I'd say it's ambiguous and you should notate in a way to avoid ambiguities. Especially if you're in the camp of multiplication like
a(b)being different fromaband/ora × b.SmartmanApps@programming.dev · -3 pts · 236d
Yes there is, as found in Maths textbooks the world over
Maths textbooks write it that way
Yes you would.
Same same
Here's one I prepared earlier to save you the trouble
And you'd be wrong
The context is Maths, you have to obey the rules of Maths. a(b+c)=(ab+ac), 5(8-5)=(5x8-5x5).
And you'd be wrong about that too
It already is notated in a way that avoids all ambiguities!
That's not Multiplication, it's Distribution, a(b+c)=(ab+ac), a(b)=(axb).
Nope, that's exactly the same, ab=(axb) by definition
(axb) is most certainly different to axb. 1/ab=1/(axb), 1/axb=b/a
JackbyDev@programming.dev · 3 pts · 236d
Please read this section of Wikipedia which talks about these topics better than I could. It shows that there is ambiguity in the order of operations and that for especially niche cases there is not a universally accepted order of operations when dealing with mixed division and multiplication. It addresses everything you've mentioned.
https://en.wikipedia.org/wiki/Order_of_operations#Mixed_division_and_multiplication
MotoAsh@piefed.social · 5 pts · 253d
Well, now you might be running into syntax issues instead of PEMDAS issues depending on what they're confused about. If it's 12 over 2*6, it's 1. If it's 12 ÷ 2 x 6, it's 36.
A lot of people try a bunch of funky stuff to represent fractions in text form (like mixing spaces and no spaces) when they should just be treating it like a programmer has to, and use parenthesis if it's a complex fraction in basic text form.
Feathercrown@lemmy.world · 3 pts · 253d
The P in PEMDAS means to solve everything within parentheses first; there is no "distribution" step or rule that says multiplying without a visible operator other than parentheses comes first. So yes, 36 is valid here. It's mostly because PEMDAS never shows up in the same context as this sort of multiplication or large fractions
SmartmanApps@programming.dev · -2 pts · 236d
and without a(b+c)=(ab+ac), now solve (ab+ac)
It's a LAW of Maths actually, The Distributive Law.
It's not "Multiplying", it's Distributing, a(b+c)=(ab+ac)
No it isn't. To get 36 you have disobeyed The Distributive Law, thus it is a wrong answer
people like you try to gaslight others that there's no such thing as The Distributive Law
Feathercrown@lemmy.world · 1 pts · 235d
Are you under the impression that atomizing your opponents statements and making a comment about each part individually without addressing the actual point (how those facts fit together) is a good debate tactic? Because it seems like all you've done is confuse yourself about what I was saying and make arguments that don't address it. Never mind that some of those micro-rebuttals aren't even correct.
SmartmanApps@programming.dev · 0 pts · 236d
Yes they do, because not every division is a fraction
JackbyDev@programming.dev · 1 pts · 236d
https://math.berkeley.edu/~wu/order5.pdf
SmartmanApps@programming.dev · -1 pts · 236d
I already said he was wrong about that. Quoting him saying it doesn't change that he's wrong about it
JackbyDev@programming.dev · 2 pts · 236d
Take it up with Berkeley then.
sukhmel@programming.dev · 0 pts · 252d
Treat
a + b/c + dasa + b/(c + d)I can almost understand, I was guilty of doing that in school with multiplication, but auto-parenthesising the first part is really crazy take, imoJackbyDev@programming.dev · 1 pts · 252d
That's a really odd way to parse it.
SmartmanApps@programming.dev · 0 pts · 236d
No don't. That rule was changed more than 130 years ago. a+b/c+d=a+(b/c)+d, Division before Addition
Zephorah@discuss.online · 5 pts · 253d
Alternatively, the poster calculated the wrong answer, thus assuming this guy was wrong.
pixeltree@lemmy.blahaj.zone · 2 pts · 253d
Gotcha gotcha, sorry
Ghyste@sh.itjust.works · -1 pts · 253d
DragonTypeWyvern@midwest.social · 8 pts · 253d
This shit take got deleted right in front of my eyes
The system works
SSUPII@sopuli.xyz · 1 pts · 253d
Oh so just like me on !lemmyshitpost@lemmy.world
Truscape@lemmy.blahaj.zone · 87 pts · 253d
Presuming PEMDAS is our order of operations and the 5 next to the parentheses indicates multiplication...
2+5(8-5) -> 2+5(3) -> 2+15=17
Other than adding a multiplication indicator next to the left parentheses for clarification (I believe it's * for programming and text chat purposes, a miniature "x" or dot for pen and paper/traditional calculators), this seems fine, yeah.
...I worry about how many people may not understand how to solve equations like these.
ftbd@feddit.org · 36 pts · 253d
That's not even an equation, just basic arithmetic
Cethin@lemmy.zip · 9 pts · 253d
Technically not algebra, right? Algebra is where you move things around and solve for variables, and that kind of thing. This is just arithmetic.
ftbd@feddit.org · 7 pts · 253d
You're right, that's what I meant. Fixed it, thanks!
SmartmanApps@programming.dev · 0 pts · 236d
No, it actually is Algebra. The Distributive Law isn't taught to students until they start on Algebra.
There's no a(b+c) in Arithmetic.
Cethin@lemmy.zip · 2 pts · 236d
I don't think you're right. The wiki page literally uses a similar equation as an example of "elementary arithmetic." It also uses a similar one, but with variables, as an example in "elementary algebra." That implies that yes, this is arithmetic, and the introduction of variables is what makes it algebra.
It doesn't matter what course finally teaches it to you. That could be just out of convenience, not by definition part of that domain. It's been ages since I took it, though I could swear I learned this in pre-algebra (meaning before algebra), or earlier. I could be wrong on this though. Again, it's been a very long time.
SmartmanApps@programming.dev · -3 pts · 236d
You don't think Maths textbooks are right??
is full of disinformation. Note that they literally never cite any Maths textbooks
And whichever Joe Blow My Next Door Neighbour wrote that is wrong
Algebra isn't taught until high school
No, anything with a(b+c) is Algebra, taught in Year 7
and the rules of Algebra, which includes a(b+c)=(ab+ac). There is no such rule in Arithmetic.
It does if you're going to argue over whether it's Arithmetic or Algebra.
The Distributive Law is 100% part of Algebra. It's one of the very first things taught (right after pronumerals and substitution).
I teach it. We teach it to Year 7, at the start of Algebra
Cethin@lemmy.zip · 2 pts · 236d
You're very rude. Also, Ill informed, and you think you're smarter than you are. For example, this:
Elementary doesn't mean elementary school. Do you think elementary particles are the ones they teach you in elementary school? Lol. Elementary means fundamental or basic.
SmartmanApps@programming.dev · -1 pts · 236d
What do you expect to happen when you call a Maths teacher wrong about Maths?
Maths teachers are ill informed about Maths?? 😂
Which therefore contradicts your argument about it being part of Arithmetic, which is taught in elementary school, Algebra isn't
Truscape@lemmy.blahaj.zone · 6 pts · 253d
Fair enough, I've heard "math problem" and "math equation" used interchangeably.
Also you would be surprised how many people do not know basic algebra, at least in the US rofl
upandatom@lemmy.world · 2 pts · 253d
You. You are one of them bc you do not know what an equation is.
There is no algebra here. This is arithmetic.
Truscape@lemmy.blahaj.zone · 3 pts · 253d
When I made my example, I used an algebraic expression, but yeah, the original question was arithmetic, sorry. Not very good at explaining things XD
SmartmanApps@programming.dev · -2 pts · 236d
No, it's actually Algebra. There is no a(b+c) in Arithmetic
SmartmanApps@programming.dev · -2 pts · 236d
You are one of the people who doesn't know what a(b+c) is
Yes there is, 5(8-5).
There's no a(b+c) in Arithmetic
MonkderVierte@lemmy.zip · -2 pts · 253d
Algebra has horrible syntax. Way too much implications.
Septimaeus@infosec.pub · 0 pts · 252d
Implications or assignment? They didn’t specify notation.
SmartmanApps@programming.dev · 0 pts · 236d
Umm, neither?? 😂
a(b+c)=(ab+ac) is taught in Algebra, The Distributive Law, it can't mean anything else - it's the reverse operation to Factorising ab+ac=a(b+c).
Septimaeus@infosec.pub · 1 pts · 235d
I know. I was clowning on the dude mad about the arrows by offering one of numerous other meanings outside Boolean Algebra that sounded even more absurd in that context.
SmartmanApps@programming.dev · -1 pts · 235d
Ok, fair enough. Some people seriously believe completely wrong things. A smiley goes a long way to showing intent
SmartmanApps@programming.dev · -2 pts · 236d
Basic Algebra actually. Students aren't taught the Distributive Law until they start on Algebra
TheRedSpade@lemmy.world · 14 pts · 253d
While I never failed a math class, I also never went past high school. When would your presumptions NOT be true?
Truscape@lemmy.blahaj.zone · 7 pts · 253d
Some forms of programming syntax, although there are the fringe cases where an equation (or function in programming) is represented by a symbol in conjunction with a parentheses input.
For example:
y(x) = 2*x+3
5+y(1) = 10, as 1 is substituted in for x in the prior equation.
TheBlackLounge@lemmy.zip · 3 pts · 253d
And in some languages a number can be used as a name of a variable or a function, so it can be anything really
MotoAsh@piefed.social · 2 pts · 253d
Not in most programming languages, though. You cannot start names with a number. Unless you're using some strange character that merely looks like a number, anyways. Programming with unicode can get weird but generally works without issue these days.
SmartmanApps@programming.dev · 0 pts · 236d
Not in Maths it can't
No, it can only be a Factorised Term, ab+ac=a(b+c). You also can't call a function by any letter that you've used as a pronumeral
moriquende@lemmy.world · 1 pts · 253d
Wouldn't we just assume function expressions are always "in parenthesis"? Then it's just a substitution and no rules were changed.
SmartmanApps@programming.dev · 0 pts · 236d
No, because factorised Terms also are, ab+ac=a(b+c).
moriquende@lemmy.world · 2 pts · 236d
But factorised terms are multiplications, so they're still following the same rules: a(b+c) = a*(b+c)
Example: 2(3+5)=16, and also 2*3+2*5=16
SmartmanApps@programming.dev · -3 pts · 236d
No, they're Distribution done in the Brackets step, a(b+c)=(ab+ac), now solve (ab+ac)
Nope! a(b+c)=(ab+ac). 1/a(b+c)=1/(ab+ac), but 1/ax(b+c)=(b+c)/a.
(2x3+2x5) actually, or you'll get the wrong answer when it follows a Division sign. See previous point
moriquende@lemmy.world · 3 pts · 236d
Nope, that's wrong. See https://www.wolframalpha.com/input?i=10%2F2%282%2B3%29 for reference.
Alaknar@sopuli.xyz · 7 pts · 253d
Multiplication sign is not required in situations like this. Same with unknowns - you don't have to write
2*x, you just write2x.SmartmanApps@programming.dev · -1 pts · 236d
No, it indicates Distribution, a(b+c)=(ab+ac), 5(8-5)=(5x8+5x5).
DarkCloud@lemmy.world · -22 pts · 253d
I prefer BM-DAS, no one's out here doing exponents, and no one calls brackets "parentheses"...
cobysev@lemmy.world · 23 pts · 253d
The way I was taught growing up, brackets are [these]. Parenthesis are (these).
Yes, technically the latter are also brackets. But they can also be called parenthesis, whereas the former is exclusively a bracket. So we were taught to call them separate words to differentiate while doing equations.
Droggelbecher@lemmy.world · 8 pts · 253d
I'm a theoretical physics grad student and a night school maths teacher, I have never heard this distinction. People in academia around me call them round and square brackets.
tigeruppercut@lemmy.zip · 9 pts · 253d
It's a US vs UK (and probably others) distinction. The ( ) are almost never called brackets in the US, unless it's a regional thing I'm not aware of. Also the [ ] didn't get used in any math classes I was in the US up through calculus except for matrices.
Droggelbecher@lemmy.world · 3 pts · 253d
Interesting! Nobody at my institute is a native English speaker. They're from several European and some Asian and south American countries.
DarkCloud@lemmy.world · 2 pts · 253d
Yeah, but as an adult it depends entirely on whether you're in an industry or hobby that requires that level of bracket nuance/exponents.
Most of us are just trying to remember the basics.
SmartmanApps@programming.dev · -3 pts · 236d
They're all brackets. Parentheses is actually the part inside the ().
Deebster@infosec.pub · 1 pts · 253d
I learnt it as BODMAS (brackets, orders, division and multiplication, addition and subtraction).
Edit: I see we're repeating points from the earlier posts down there 👇 (with default sort).
Triasha@lemmy.world · 77 pts · 253d
Pemdas, parenthesis first, for a total of 3. Then multiplication, 15, then addition. 17. What's hard about this?
ExtremeDullard@piefed.social · 63 pts · 253d
5 isn't a valid function name, is obviously the right answer.
TheRedSpade@lemmy.world · 17 pts · 253d
How can you be sure it's not defined when we only see one line?
Voroxpete@sh.itjust.works · 7 pts · 253d
They didn't say it's not defined, they said it's not a valid name. Most languages don't allow function names to start with a number, so 5 literally cannot be a function if that's the case.
But that's assuming this isn't some really obscure language.
SmartmanApps@programming.dev · -2 pts · 236d
No, but it can be and is a coefficient of the Term 5(8-5)
gnutrino@programming.dev · 3 pts · 253d
It could be a Church Numeral
marcos@lemmy.world · 1 pts · 253d
I'm pretty sure that's a module operator...
merc@sh.itjust.works · 0 pts · 253d
Depends on the language.
SmartmanApps@programming.dev · -2 pts · 236d
No it doesn't
merc@sh.itjust.works · 0 pts · 236d
Yes it does.
SmartmanApps@programming.dev · -1 pts · 235d
Says person who can't cite a single example of it depending on the language 🙄
SmartmanApps@programming.dev · -1 pts · 236d
5 is a coefficient of the Term 5(8-5) is the correct answer
banshee@lemmy.world · 54 pts · 253d
I'm sorry but isn't this elementary school math?
jjjalljs@ttrpg.network · 45 pts · 253d
I got some people really angry at me when I suggested writing some math expression with parenthesis so it would be clearer. I think someone told me that order of operations is like a natural law and not a convention, and thus everyone should know it or be able to figure it out.
stray@pawb.social · 16 pts · 253d
I sometimes like to add unnecessary parentheses or brackets to section things off and improve legibility, but I don't do any math stuff collaboratively, so I have no idea whether others would find that disruptive or helpful.
Feathercrown@lemmy.world · 5 pts · 253d
I do this, sometimes it helps reveal a natural pattern when some parts of earlier terms have "disappeared" to simplification
Alaknar@sopuli.xyz · 11 pts · 253d
I mean, there are very few ambiguous cases when you know how the order of operations works.
SmartmanApps@programming.dev · 0 pts · 236d
There are precisely none which are ambiguous
Quatlicopatlix@feddit.org · 5 pts · 253d
Using parenthesis can really help if you want to simplify a term or need to rewrite something. I do that all the time because a lot of times you then can just cross stuff out fast on equations or get a common term that just has some factor instead of having a convolutet equation.
merc@sh.itjust.works · 5 pts · 253d
I got really angry because the prettier code formatter insists on removing parentheses, making things less clear. Because it's an "opinionated" formatter you can't tell it not to do that without using ugly hacks.
Sure, logically there are times when you don't need them. But, often it helps to explain what's happening in the code when you can use parentheses to group certain things. It helps in particular when you want to use "&&" and "||" to say "do X only if Y fails".
jjjalljs@ttrpg.network · 5 pts · 253d
I think you can do
// prettier-ignore, because I remember facing that exact situation.https://prettier.io/docs/ignore/
merc@sh.itjust.works · 2 pts · 252d
I've done that, but that's ugly.
87Six@lemmy.zip · 1 pts · 253d
SmartmanApps@programming.dev · -1 pts · 236d
That's because it's already clear as is, as per the rules of Maths.
It's a natural consequence of the definitions of the operators. e.g. Multiplication is shorthand for repeated Addition - 2x3=2+2+2 - so if you don't do it before addition you end up with wrong answers. The order of operations rules is in fact just breaking everything down into Addition and Subtraction and then solving from there.
There are some conventions, like left to right, but in that case that's only because students tend to make mistakes with signs when they don't go from left to right, so it's there to preserve teachers sanity.
jjjalljs@ttrpg.network · 0 pts · 236d
More people evaluate
2+3x4incorrectly than2+(3x4). So, no, your answer does not hold up to my observed reality. You can throw as many "well technically" and "well actually" as you want, but that's not going to fix the bug or make a pr.brown567@sh.itjust.works · 39 pts · 253d
2 5 8 5 - × + for you RPN fans =)
silver_wings_of_morning@feddit.dk · 34 pts · 252d
Any PEMDAS enjoyers in chat?
I_Fart_Glitter@lemmy.world · 32 pts · 253d
PEMDAS bitches.
KyuubiNoKitsune@lemmy.blahaj.zone · 17 pts · 253d
It's interesting that you can somewhat tell where you are from based on this, I learned it as BODMAS
radioactivefunguy@piefed.ca · 6 pts · 253d
O - oxponent?
KyuubiNoKitsune@lemmy.blahaj.zone · 14 pts · 253d
Orders.
Brackets, Orders (powers and roots), Division, Multiplication, Addition, and Subtraction
Alaknar@sopuli.xyz · 3 pts · 253d
This is fucking so many people over... It should be limited - like Orders - to only Multiplication and Addition.
Because division is the same operation as multiplication, and subtraction is the same operation as addition, and they have the same "weight" in the order of operations (meaning, you do them left-to-right).
KyuubiNoKitsune@lemmy.blahaj.zone · 2 pts · 253d
Another commenter mentioned something similar, how they're interchangeable, but I'm not sure why you say it's fucking people over.
Alaknar@sopuli.xyz · 4 pts · 253d
Because the people who learn "DM" or "MD" then spend hours online arguing that you must do one before the other.
KyuubiNoKitsune@lemmy.blahaj.zone · 2 pts · 253d
People do be arguing, lol
moriquende@lemmy.world · 2 pts · 253d
Did you mean MD and DM?
SmartmanApps@programming.dev · 0 pts · 236d
Because you don't want people to know when to do Division and Subtraction? 😂
No it isn't, but they are both binary operators.
And where are they going to do Division and Subtraction in the left to right if you've left them out? 🙄
Alaknar@sopuli.xyz · 1 pts · 236d
Because division is multiplication, and subtraction is addition.
2/2is the same as2*½2-2is the same as2+(-2)Well, as I already said multiple times: Division = Multiplication and Subtraction = Addition, therefore they would be doing them together, left to right. As in:
9-3+2would not confuse anyone who learned "Addition → Subtraction", as it does right now.SmartmanApps@programming.dev · 0 pts · 236d
No it isn't.
And you still have to do both
They're equal in value, they're not the same
You got that the wrong way around. Brackets have only been used in Maths for a few centuries now
And you were wrong every time you said it.
Not if you left them out of the mnemonic and they didn't know when to do them
SmartmanApps@programming.dev · 0 pts · 236d
To the Order of. 2² is 2 to the order of 2
sbeak@sopuli.xyz · 3 pts · 253d
I learned BODMAS too! It seems BIDMAS is another one (British I think), PEMDAS is the weird American one, BEDMAS is a thing too. You're able to vary the first letter (parenthesis or brackets), second letter (indices/exponent/"order" or "operation"), and the order of multiplication/division (MS or SM) and addition/SUBTRACTION (AD or DA)
Very interesting indeed.
KyuubiNoKitsune@lemmy.blahaj.zone · 2 pts · 253d
We need a super position of all of them.
Endmaker@ani.social · 1 pts · 253d
Where are pemdas and bodmas users from?
DavidGA@lemmy.world · 6 pts · 253d
Pemdas, USA. Bodmas, UK.
azi@mander.xyz · 3 pts · 253d
BEDMAS, Canada
KyuubiNoKitsune@lemmy.blahaj.zone · 2 pts · 253d
I think most former British colonies use BODMAS
Creat@discuss.tchncs.de · 3 pts · 253d
But the USA seems to use PEMDAS? I'm confused now...
DragonTypeWyvern@midwest.social · 3 pts · 253d
They mean Commonwealth countries more precisely
KyuubiNoKitsune@lemmy.blahaj.zone · 3 pts · 253d
Yeah, my bad
KyuubiNoKitsune@lemmy.blahaj.zone · 2 pts · 253d
It talks about it here:
https://en.wikipedia.org/wiki/Order_of_operations#Mnemonics
anamethatisnt@sopuli.xyz · 9 pts · 253d
I never ran into PEMDAS while growing up, in Sweden I've always been taught of it as the following order of operations:
Truscape@lemmy.blahaj.zone · 14 pts · 253d
Technically roots are a form of exponent, just fractional (square root is power of 1/2, for instance). I can see how it could be easier to conceptualize when you break it down like that though. Neat to see the differences compared to the US breakdown :)
anamethatisnt@sopuli.xyz · 2 pts · 253d
Technically we go for 2. Powers & Roots, I just didn't want to break the PEMDAS when comparing. :)
DragonTypeWyvern@midwest.social · 4 pts · 253d
That's PEMDAS...
Saapas@piefed.zip · 1 pts · 251d
They aren't using the same words so the shorthand (if they have one) is different. I don't think we had a shorthand for it either, we just learned it.
And we learned them in groups numbered like the Swedes
DragonTypeWyvern@midwest.social · 1 pts · 251d
Okay then, but, fun story, the BODMAS they're talking about is also just PEMDAS using different words and a different listed order for multiplication/division, with the understanding that it's more properly PE(MD)(AS)
The order of operations is the important bit and everyone learns it that way. What causes the arguments is when dummies online forget that M+D or A+S can theoretically be done properly in any order and that part is a matter of preference.
Saapas@piefed.zip · 2 pts · 251d
The disadvantage of a shorthand compared to just a numbered list might be that people think it's strictly one after the another instead of groups
stray@pawb.social · 3 pts · 253d
e: Wanted to see if this is a thing in English.
agedcorn@lemmy.world · 5 pts · 253d
Please Excuse My Dear Aunt Sally... bitches.
funkless_eck@sh.itjust.works · 4 pts · 253d
crmsnbleyd@sopuli.xyz · 30 pts · 252d
Let's not do engagement bait here 😭
nialv7@lemmy.world · 23 pts · 252d
Precedences are just made up social constructs, don't let the system restrict you, you can evaluate this expression however you want. Go wild.
vala@lemmy.dbzer0.com · 22 pts · 253d
Hope some LISP can clear this up
Edit:
DaMonsterKnees@lemmy.world · 21 pts · 253d
I'm not seeing a single mention of My Dear Aunt Sally. The youth are lost...
beneeney@lemmy.zip · 31 pts · 253d
Aunt Sally said some racist things at Thanksgiving, I'm tired of excusing her smh
GlendatheGayWitch@lemmy.world · 5 pts · 253d
Already saying racist things this early in the morning? (It's Thanksgiving in the US today)
zebidiah@lemmy.ca · 9 pts · 253d
You're drunk Sally, go to bedmas!
callouscomic@lemmy.zip · 7 pts · 253d
I'll never understand these approaches to learning. They require remembering the phrase, and then require remembering how the phrase translates to the rules you need to remember.
I'll just remember the rules in the first place. Less effort.
tigeruppercut@lemmy.zip · 20 pts · 253d
There's just no way rote learning is easier than mnemonics unless you have a photographic memory.
Shit, I still remember the order of taxonomic ranks after seeing the phrase "King Phillip came over from Germany stoned" written in a used bio textbook 30 years ago when we never even made it to that chapter to officially study in class. I guarantee I never would've remembered the list "kingdom phylum class order family genus species".
oatscoop@midwest.social · 4 pts · 253d
Don't ask anyone over the age of 45 how they remember resistor color codes ...
tigeruppercut@lemmy.zip · 2 pts · 252d
I'm going with this one: Batman blows Robin on yon Gotham bridge; Vows Gordon's next.
But wiki has a list:
https://en.wikipedia.org/wiki/List_of_electronic_color_code_mnemonics#Offensive/outdated
Looks like it's mostly in ROY G BIV order, although you've got black and brown up front, then they drop indigo and add gray and white at the end.
dankm@lemmy.ca · 3 pts · 252d
Warning: my music nerd's about to come out.
I'm in my 40s, and have been playing music since single digits. I still remember the order of lines in the staffs with "Every Good Boy Deserves Fudge", "FACE", "Good Boys Deserve Fudge Always", and "All Cows Eat Grass". I did teach my kids "Good Burritos Don't Fall Apart", though, since they seem to like burritos.
My internal math nerd agrees with the grandparent though, for some reason I just remembered the order of operations and was confused when my kids came home with PEDMAS. But to be fair, I use the order of operations every day at work, so 🤷. I'm also one of those people who will insist on using parentheses everywhere there's more than two terms, though, so take from that what you will.
PoisonTheWell@reddthat.com · 4 pts · 253d
https://en.wikipedia.org/wiki/Mnemonic?wprov=sfla1
IcyToes@sh.itjust.works · 2 pts · 253d
Yeah, but there is more to remember. I remember BODMAS and if I forget the rules, I work it out and apply it.
SmartmanApps@programming.dev · 0 pts · 236d
Yeah, exactly, but the U.S. seems to have a chip on it's shoulder about always doing everything differently to the whole rest of the world. "Maths? We're not going to use BEDMAS, and we're not going to call them Brackets, and...".
Digit@lemmy.wtf · 18 pts · 253d
Hrmm.
I read that as resulting in 21.
My education system did fail me.
I plugged that into ghci as 2+5*(8-5), and it says 17.
:(
I did (2+5)*(8-5).
Doh.
[Edit: (Double doh! Mistyped that here as 5+2. XD)]
A_Chilean_Cyborg@feddit.cl · 19 pts · 253d
You do parenthesis first and then multiplications and then sums, you did parenthesis, then sums, then multiplications, wich is wrong.
merc@sh.itjust.works · 1 pts · 253d
You don't necessarily have to do parentheses first. What matters is that the things inside the parentheses are a group that you can't break apart. If you have
10÷2+3-2*(2+1)you can do the division first5+3-2*(2+1)then the addition outside the parentheses8-2*(2+1)It's just that before you do the multiplication of the term outside the parentheses, you have to handle the parentheses group, so you get8-2*3->8-6->2SmartmanApps@programming.dev · 0 pts · 236d
Yes, you do necessarily have to do it first
And outside, and you must do them first. You haven't finished Brackets until you have 5(8-5)=15.
only because you've separated that part with a plus sign
SmartmanApps@programming.dev · 0 pts · 236d
There aren't any, only Addition and Brackets (and Subtraction inside Brackets)
A_Chilean_Cyborg@feddit.cl · 1 pts · 236d
Uh huh.
Nils@lemmy.ca · 9 pts · 253d
You might want to report that error. Or, did you mean 2+5*(8-5)?
Digit@lemmy.wtf · 7 pts · 253d
Oops! Typo. School failed me hard!
[Edit: Thanks. Corrected that.]
victorz@lemmy.world · 2 pts · 253d
How far along in school are you btw?
Digit@lemmy.wtf · 1 pts · 252d
over 20 years past giving up on school [in 2nd year of college], when they kept failing me.
victorz@lemmy.world · 1 pts · 251d
Aha.
Cavemanfreak@lemmy.dbzer0.com · 9 pts · 253d
The problem is you can't just add parenthesis willy nilly, that breaks the whole equation!
ivanafterall@lemmy.world · -5 pts · 253d
Well, it used to be a free country until common core and now this nonsense is the result. Numbers and punctuation mixed together. Pure chaos.
DarrinBrunner@lemmy.world · 16 pts · 252d
My education system didn't fail me, I failed it.
ViperActual@sh.itjust.works · 14 pts · 252d
2+5(8-5)
For anyone wanting to see a different way of solving it with distribution:
2+58-55 2+40-25 42-25 17
So long as you follow the basic math rules, you can solve it in many different ways to get the same result.
PlexSheep@infosec.pub · 14 pts · 253d
This is an antimeme
MattW03@lemmy.ca · 13 pts · 253d
Let's keep it easy. There's 2 + all the other number who results in 15 = 17.
Someone may mistake by doing 2+5 then the rest of the operation, resulting in 21. But is wrong.
Paradachshund@lemmy.today · 11 pts · 253d
The high-and-mightiness quotient in this thread is reaching critical levels
psx_crab@lemmy.zip · 10 pts · 253d
Obviously the answer is 2+x(y)
anamethatisnt@sopuli.xyz · 4 pts · 253d
And even if you don't simplify it to y the end result is the same
2+x(y-z) = 2+xy-xz
MrSmith@lemmy.world · 0 pts · 253d
I don't know why, but this was intuitively my first approach. Eve though it's much simpler than that.
SmartmanApps@programming.dev · 0 pts · 236d
Because that's what we teach students to do, though technically it should be (xy-xz)
Tithen@anarchist.nexus · 9 pts · 253d
Was anyone else ever taught it as BOMDAS as opposed to BODMAS?
Jayve@lemmy.world · 16 pts · 253d
PEMDAS, is that the same as BOMDAS?
marcos@lemmy.world · 4 pts · 253d
Why do people put bot pairs of multiplication and division, and addition and subtraction on the acronym?
Do you really follow that order with the associative operations?
dreadbeef@lemmy.dbzer0.com · 5 pts · 253d
do you think i know what an associative operation is?
SmartmanApps@programming.dev · 0 pts · 236d
Because it's intended to be used as a checklist
Yep
Nindelofocho@lemmy.world · 4 pts · 253d
BOMDAS deez nuts or something
Tithen@anarchist.nexus · 2 pts · 253d
I think so. Amazing how many different ways there are to say it
Notyou@sopuli.xyz · 2 pts · 253d
So instead of Parentheses, Exponents is it Box and O that digit in the sky?
merc@sh.itjust.works · 2 pts · 252d
Brackets and Orders, not that anybody calls "(" a bracket or "^" an "order".
SmartmanApps@programming.dev · 0 pts · 236d
It's "to the order of" actually. 2² is 2 to the order of 2
Yes we do. They're ALL Brackets - square, round, squiggly...
SmartmanApps@programming.dev · 0 pts · 236d
They're all just different mnemonics for the same rules.
Peppycito@sh.itjust.works · 11 pts · 253d
It was BEDMAS for us, where the E was exponents or something.
NikkiDimes@lemmy.world · 1 pts · 253d
Found the Canadian
SmartmanApps@programming.dev · 0 pts · 236d
Nope, it's the same in Australia and the U.K.
NikkiDimes@lemmy.world · 2 pts · 236d
Sorry, found the Commonwealther
SmartmanApps@programming.dev · 0 pts · 236d
Or more precisely, the non-USer 😜
NikkiDimes@lemmy.world · 2 pts · 236d
Okay, sorry, found the person from a sane country 😂
Alaknar@sopuli.xyz · 5 pts · 253d
There's no difference.
Addition and subtraction are the same operation, multiplication and division are the same operation.
So:
BO(MD)(AS) == BO(DM)(AS)
EDIT: in order to stop confusing people, it should just be: BOMA.
SmartmanApps@programming.dev · 0 pts · 236d
No they're not, but they are both binary operators.
Leaving out D and S confuses people about where to do them in the order. It's intended to be used as a checklist
Alaknar@sopuli.xyz · 0 pts · 236d
You already said that to me. I replied here.
SmartmanApps@programming.dev · 0 pts · 235d
And you're still ignoring it
Alaknar@sopuli.xyz · 0 pts · 235d
What do you mean? I replied to it...
SmartmanApps@programming.dev · -1 pts · 235d
Where you, yet again, ignored that I told you what you said is wrong, as per Maths textbooks
princessnorah@lemmy.blahaj.zone · 2 pts · 253d
Yeah, I was taught BOMDAS here in Australia.
AndyMFK@lemmy.dbzer0.com · 3 pts · 253d
I was taught BODMAS in Australia
SmartmanApps@programming.dev · 0 pts · 236d
BODMAS (or BEDMAS), not BOMDAS. (unless they did that in some random state). I'm an Australian Maths teacher
princessnorah@lemmy.blahaj.zone · 1 pts · 234d
Or it was some random teacher. Or it was more than fifteen years ago. I dunno, it was just what I was taught.
SmartmanApps@programming.dev · 2 pts · 233d
Yeah, maybe. My Year 7 students, who have come fresh to me from Year 6, use BEDMAS, and I teach BEDMAS for consistency (I also think it's a better acronym anyway - think of a massive 4-poster bed to ingrain the idea of BED-MAS)...
Evil_Shrubbery@thelemmy.club · 2 pts · 253d
I was taught only Brackets Division Subtraction Multiplication at the local dungeon.
(I still have the student loans to prove it.)
essell@lemmy.world · 2 pts · 253d
Its BODMAS for maths and BOMDAS for twerking.
Easy mistake to make given the amount of maths involved in dancing.
SmartmanApps@programming.dev · -1 pts · 236d
I don't think so, and I've seen Maths textbooks from all over the world. Only the U.S. wants to reverse the order of DM from everyone else's acronym. 🙄
Xylight@feddit.online · 8 pts · 253d
My dumbahh did 2+5 like it was in parentheses and got 21
MrSmith@lemmy.world · 8 pts · 253d
To all the people yelling PEMDAS and BOMBDAS or whatever - languages other than English exist.
Kenny2999@lemmy.world · 8 pts · 253d
Syntax error
SmartmanApps@programming.dev · 1 pts · 236d
Nope! The Distributive Law
Kenny2999@lemmy.world · 0 pts · 236d
Depends on the language if "5(" gets interpreted as "5×(". I guess mostly no.
SmartmanApps@programming.dev · 0 pts · 236d
No it doesn't.
Always no. The Distributive Law, a(b+c)=(ab+ac).
Kenny2999@lemmy.world · 0 pts · 236d
You're talking math, I'm talking programming languages. We are not the same. Most languages throw a syntax error if the multiplication symbol is missing.
SmartmanApps@programming.dev · 0 pts · 236d
Written by people who forget the order of operations rules, hence MathGPT is the only e-calc which gives correct answers.
Yep, as well as being a programmer I'm also a Maths teacher
See first point
Kenny2999@lemmy.world · 1 pts · 236d
Well, 8 ppl got my joke 2 weeks ago. Thats not bad for someone who had to get a real job after the phd.
sangriaferret@sh.itjust.works · 7 pts · 253d
The education system did not fail me. I failed my education.
Saapas@piefed.zip · 3 pts · 251d
Something funny about everyone being so eager to show how they can solve this
Daft_ish@lemmy.dbzer0.com · 3 pts · 251d
You have to subtract the numbers with the most flat sides first and divide by the number of pennies in your sock drawer.
pewgar_seemsimandroid@lemmy.blahaj.zone · 3 pts · 253d
the answer is [Answer]
MarriedCavelady50@lemmy.ml · 2 pts · 253d
Lemminary@lemmy.world · 3 pts · 253d
67
Gullible@sh.itjust.works · 4 pts · 253d
Hut hut!
AtariDump@lemmy.world · 2 pts · 253d
HIKE!
elevenbones@piefed.social · 1 pts · 212d
Damn, its always the simple math problem post with like, almost 700 comments lmao
cmhe@lemmy.world · -2 pts · 252d
I don't get why these kind of post crop up so often.
The answer to them doesn't matter and these aren't really math questions, because there is no context given. This is just endless discussions about different people having different assumptions on notation used there...
In real math, where the numbers mean something, good and consistent notation is important, but not necessary, because the order of operations or what those operations are exactly would be clear through the context of these formulas. Good notation just makes it easier to spot errors, work with formulas or to avoid confusion.
Here is what I would assume this formula could mean. Someone has 2 apples and 5 bags of apples that initially came with 8 apples each inside, but someone else ate 5 apples from each of these bags.
With this context it is pretty clear what the answer would be.
Sertou@lemmy.world · -6 pts · 253d
Or it simply could be that I haven't needed to concern myself with the order of operations more than a dozen times since high school. Even when working as a web coder it was so seldom necessary that I can't recall a single example.
The US education system was still pretty decent when I was in middle and high school in the 1980s, so we definitely covered this in algebra.
WorldsDumbestMan@lemmy.today · -8 pts · 253d
That's so evil and subtle. It took me multiple attempts to figure it out. You have to have quite the sharp eye to realize: no, you do not stop at calculating the numbers in parantesis first. You don't add the resulting numbers, there is no +/- operator, so the number in parantesis is the power of the number before it. But wait! if You calculated 2+5 = 7 * 3 and hot 21, you are wrong. Remember that multiplication goes first, so it's: 2+5(8-5) = 2+5*3=2+15=17
nomorebillboards@lemmy.world · -10 pts · 253d
But 2 + 5 + 8 - 5 is 16 - 5 which is 11
Kolanaki@pawb.social · -17 pts · 252d
2+5 is 8, 8-5 is 3. 8×3 is 24.
But I also haven't done this kind of math since 4th grade so I'm not sure if the joke is that this is the real answer or the answer you get doing it wrong... 🤔
x4740N@lemmy.world · -22 pts · 253d
Its because its:
My calculator app automatically added it when typing in what was in the image and "2+5×(8−5)" does equal 17.
It's absolutely the fault of the person making the social media media post for not writing it properly and confusing people.
ilinamorato@lemmy.world · -22 pts · 253d
it'sa badlywrittenmathproblemSeriously, every time this comes up and everyone makes a huge deal out of it, I keep thinking, "none of the people writing these better be teachers." You have to be more clear than this.
Edit: ok, not so much this one. I just read the words and assumed the math problem was one of the ambiguous ones. Stand down, soldiers.
SereneSadie@quokk.au · -31 pts · 253d
Dekkia@this.doesnotcut.it · 23 pts · 253d
Counterpoint:
If kids where taught how to solve them properly we wouldn't need to dumb down equasions.
SmartmanApps@programming.dev · 0 pts · 236d
They are taught how to solve them properly. It's only adults who've forgotten the rules of Maths who get them wrong
prole@lemmy.blahaj.zone · 20 pts · 253d
What? A number next to parenthesis always means multiplication. Are people really not taught this anymore?
x4740N@lemmy.world · 0 pts · 253d
I live in Australia and don't recall my school at all teaching me this in maths class
They taught us stuff like radius and area of a circle but not this
Edit:
Also counterpoint, people exist that live in other countries and every countries education system is different
prole@lemmy.blahaj.zone · 1 pts · 252d
I thought math was relatively universal. The US education system may be different, but I'm certain we're not the only place that does it that way.
SmartmanApps@programming.dev · 0 pts · 236d
It is
They have the same rules, but they don't require Maths teachers to have a Maths qualification (in Australia you have to have a Masters), and they have been sliding in world rankings for more than a decade.
SmartmanApps@programming.dev · 0 pts · 236d
I'm in Australia, and I remember being taught it, and I teach it.
The rules are the same everywhere, only the notation varies (in Germany they use . for multiply and : for divide, and say "dot before slash", slash being - and +).
SmartmanApps@programming.dev · 0 pts · 236d
No, it means distribution, a(b+c)=(ab+ac)
They're taught distribution yes. It's only adults who've forgotten the rules of Maths who get these wrong
Natanox@discuss.tchncs.de · 14 pts · 253d
Why should anyone do that, an implied multiplication is the normal thing you learn in (I think?) somewhere between 5th to 7th grade. You only add an operator if it's something else. It's as basic as PEMDAS.
SmartmanApps@programming.dev · -1 pts · 236d
There's no such thing. It's a Term/Product.
Yes, you learn that it's a Term/Product in Year 7
You never add an operator, or you end up with wrong answers.
Natanox@discuss.tchncs.de · 0 pts · 236d
Aaah, got it. So if I see something like "5-(2+4)" I will just remove the subtraction operator and call it a day. Smartman on the internet said so. 🥴
Also casual reminder not everyone on the internet is a native english speaker. Everyone but you knew what was meant.
SmartmanApps@programming.dev · -1 pts · 236d
Nope. Never said anything of the sort.
No I didn't, but nice try at a strawman 😂
There is no such thing as "implied multiplication" in any language. They are called Terms/Products in whatever language that book is using.
kameecoding@lemmy.world · 4 pts · 253d
Google implied multiplication.
Do you write 2x or do you write 2 • x?
That's implied multiplication, if x= (a+b) then 2x becomes 2(a+b). Implied multiplication
SmartmanApps@programming.dev · -1 pts · 236d
There's no such thing. It's a Term/Product. Google is a prime source of Maths disinformation (yes, they have been told it's wrong, repeatedly, so it's disinformation).
2a=(2xa) by definition, and 5(8-5)=(5x8-5x5).
No, that's a Term/Product.
Terms/Products
kameecoding@lemmy.world · 0 pts · 236d
I mean, I don't like to argue about this, since I am not a native English speaker, but there is an implied multiplication there.
SmartmanApps@programming.dev · -1 pts · 235d
or Factoristion, ab+ac=a(b+c) <== a Product of a and (b+c)
And yet here you are arguing with someone who is and is a Maths teacher
Nope! It's a Term/Product. There's no such thing as "implied multiplication" - you won't find it in any Maths textbook
kameecoding@lemmy.world · 0 pts · 235d
That time I didn't use the term implied multiplication I merely said that the multiplication is implied
SmartmanApps@programming.dev · -1 pts · 235d
And there's no such thing as either 🙄
SmartmanApps@programming.dev · 0 pts · 236d
Why?
Well, everyone was taught what to do with it in high school.
jaykrown@lemmy.world · -35 pts · 253d
somerandomperson@lemmy.dbzer0.com · 34 pts · 253d
are you THAT lazy
jaykrown@lemmy.world · -20 pts · 253d
somerandomperson@lemmy.dbzer0.com · 24 pts · 253d
what a fucking surprise
plant@lemmy.dbzer0.com · 17 pts · 253d
Computer please tell me I'm right
SuspiciousCatThing@pawb.social · 14 pts · 253d
Fuck everyone else I thought this was funny
blx@lemmy.zip · 6 pts · 253d
Me too! I had only scorn for the initial comment, but this response was perfect
A_Chilean_Cyborg@feddit.cl · 6 pts · 253d
So you're the guy that asked chat GPT if you could enter Chile without a passport, said yes, come to Chile and had to go back because you actually needed a passport huh?.
It surprises me the amount of people who just "outsource" their intelligence to a fking chatbot and then proceed their way in life taking moronic decisions all over, a reminder AI companies depend on people being too lazy to think to be able to sell their products.
jaykrown@lemmy.world · -11 pts · 253d
somerandomperson@lemmy.dbzer0.com · 10 pts · 253d
are you dumb?
jaykrown@lemmy.world · -5 pts · 253d
I may very well be, still researching.
MrSmith@lemmy.world · 7 pts · 253d
Coal rolling, but for IT-literate.
jaykrown@lemmy.world · -8 pts · 253d
Funny, tell that to the billionaires who have a private jet.
MrSmith@lemmy.world · 4 pts · 253d
I am. I'm also telling you.
A_Chilean_Cyborg@feddit.cl · 1 pts · 253d
Yeah? They fixed it after the fact, they always do lol.
x4740N@lemmy.world · 5 pts · 253d
You need to actually use your brain
Its like a muscle and if you don't use muscles they acclimate to the lack of use
mrgoosmoos@lemmy.ca · 3 pts · 253d
why would you post a screenshot of an AI chatbot attempting to do math?
OozingPositron@feddit.cl · 2 pts · 253d
kek
SmartmanApps@programming.dev · 1 pts · 236d
OMG! That's the first time I've actually seen AI get order of operations right! 😂