422
Glitch in the matrix
(ani.social)
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
this post was submitted on 03 Dec 2023
422 points (100.0% liked)
196
16713 readers
2201 users here now
Be sure to follow the rule before you head out.
Rule: You must post before you leave.
founded 2 years ago
MODERATORS
No. Order of operations is left to right, not right to left. 1 is wrong.
Pemdas.
Multiplication comes before division.
1 is the correct answer.
That's wrong. Multiplication and division have equal precedence, same as addition and subtraction. You do them left to right. PEMDAS could be rewritten like PE(MD)(AS). After parentheses and exponents, it"s Multiplication and division together, then addition and subtraction together. They also teach BODMAS some places, which is "brackets, order, division and multiplication, addition and subtraction" Despite reversing the division and multiplication, it doesn't change the order of operations. They have the same priority, so they are just done left to right. PEMDAS and BODMAS are the different shorthand for the same order of operations.
They were right but for the wrong reason. Implied multiplication–that is, a(b) or ab–often comes before explicit multiplication and division. Apparently it's up to the person writing the equation, so the meme is intentionally and explicitly ambiguous
They're still wrong, in my humble opinion. I'm aware of this notion, and I've even had people share a snip from some book that states this as fact. However, this is not standardized and without the convention being widely understood and recognized as the standard in the world of mathematics (which generally doesn't use the symbol (÷) at all at post-algebra levels), there is no reason to treat it as such just because a few people assert it is should be.
It doesn't make sense at all to me that implied multiplication would be treated any differently, let alone at a higher priority, than explicit multiplication. They're both the same operation, just with different notations, the former of which we use as shorthand.
There are obviously examples that show the use of the division symbol without parentheses sometimes leads to misunderstandings like this. It's why that symbol is not used by real mathematicians at all. It is just abundantly more clear what you're saying if you use the fraction bar notation (the line with numerator on top and denominator on bottom). But the rules as actually written, when followed, only reach one conclusion for this problem and others like it. x÷y(z) is the SAME as x÷y*z. There's no mathematical or logical reason to treat it differently. If you meant for the implicit multiplication to have priority it should be in parentheses, x÷(y(z)), or written with the fraction bar notation.
Implicit multiplication being before regular multiplication/division is so we can write 2y/3x instead of (2y)/(3x). Without priority, 2y/3x becomes (2y÷3)•x.
Coefficients are widely used enough that mathematicians don't want to write parentheses around every single one. So implicit multiplication gets priority.
I think one could argue a coefficient on an unknown variable, like 2y, should take higher priority simply because it cannot be any further resolved or simplified. That is not the case with, say, 2(3+1). Although that does still leave you with potential ambiguity with division/multiplication, such has 1/7y. Is the coefficient 7, or is it 1/7? i.e. Is that 1/(7y)? Or (1/7)y? Either way, if that's not the the standard understood by everyone, then it is a non-standard, inconsistent rule. And as demonstrated, if you do use that rule, it needs to be more clearly defined. That is the source of this "ambiguity". If you don't include it, the order of operations rules, as written, are clear.
Bingo!
It's the same thing, where y=3+1.
Yes, it's 1/(7y) as per the definition of Terms.
It's the standard in literally every Maths textbook.
Why the hell are you commenting on my 4 month old comments trying to argue. Fuck off.
Actually I'm educating and hoping people will stop arguing about it. You can take it on board or not. You actually nearly had it.
Also, your comments will show up in search results for all eternity unless you delete them.
I agree it needs to be more clearly defined, but one of the reasons it wasn't clearly defined was because mathematicians thought it was so universal it didn't need defining, like how parentheses work to begin with.
Casio tried not doing umplicit multiplication after some american teachers complained, then went back to doing it after everyone else complained. Implicit multiplication is the standard.
It's clearly defined in any Maths textbook you pick up.
A Maths textbook.
It's standard in every Maths textbook.
The "few people" are Maths teachers and Maths textbook authors.
There's no such thing as implicit multiplication
No, what people are calling "implicit multiplication" is either The Distributive Law - which is the first step in solving Brackets - or Terms - and neither of these things is "multiplication". Multiplication literally refers to multiplication symbols only.
The division symbol is used - it is not the same thing as a fraction bar.
No, it's the same as x÷(y*z).
Terms, The Distributive Law, are why it's treated differently.
As are you. There is no such thing as implicit multiplication - the actual relevant rules are Terms and The Distributive Law.
#MathsIsNeverAmbiguous #DontForgetDistribution
There's an argument to be made that implicit multiplication comes before division, resulting in the answer 1, but all multiplication? That's wrong, full-stop. You calculate (explicit) multiplication and division in one step, left to right. Reason being that division is technically just multiplying by the reciprocal.
There's no such thing as implicit multiplication.
1 is the correct answer, but it's because Brackets comes before Division - there is no Multiplication in this problem.
Order of operations is BEDMAS, THEN left to right within each operator.
1 is the only correct answer.