a single sentence of a wikipedia article without me handfeeding it to you
And I told you why it was wrong, which is why I read Maths textbooks and not wikipedia.
I’m sorry for your students
My students are doing good thanks
The notation is not intrinsically clear
It is to me, I actually teach how to write it.
Exactly! It’s in math textbooks, in both ways!
And both ways are explained, so not ambiguous which is which.
Ummm, I was agreeing with you??
Anyways, I’m a Maths teacher who has taught this topic many times - what would I know?
You can define your notation that way if you like
Nothing to do with me - it’s in Maths textbooks.
without knowing the conventions the author uses, it’s ambiguous
Well they should all be following the rules of Maths, without needing to have that stated.
which clearly states that the distributive property is a generalization of the distributive law
Let me say again, people calling a Koala a Koala bear doesn’t mean it actually is a bear. Stop reading wikipedia and pick up a Maths textbook.
You seem to be under the impression that the distributive law and distributive property are completely different statements
It’s not an impression, it’s in Year 7 Maths textbooks.
this certainly is not 7th year material
And yet it appears in every Year 7 textbook I’ve ever seen.
Looks like we’re done here.
If you read the wikipedia article
…which isn’t a Maths textbook!
also stating the distributive law, literally in the first sentence
Except what it states is the Distributive property, not The Distributive Law. If I call a Koala a Koala Bear, that doesn’t mean it’s a bear - it just means I used the wrong name. And again, not a Maths textbook - whoever wrote that demonstrably doesn’t know the difference between the property and the law.
This is something you learn in elementary school
No it isn’t. This is a year 7 topic. In Primary School they are only given bracketed terms without a coefficient (thus don’t need to know The Distributive Law).
be assured that I am sufficiently qualified
No, I’m not assured of that when you’re quoting wikipedia instead of Maths textbooks, and don’t know the difference between The Distributive Property and The Distributive Law, nor know which grade this is taught to.
Wikipedia is not intrinsically less accurate than maths textbooks
BWAHAHAHAHA! You know how many wrong things I’ve seen in there? And I’m not even talking about Maths! Ever heard of edit wars? Whatever ends up on the page is whatever the admin believes. Wikipedia is “like an encyclopedia” in the same way that Madonna is like a virgin.
but you are misunderstanding them
And yet you have failed to point out how/why/where. In all of your comments here, you haven’t even addressed The Distributive Law at all.
Whether you write it as a(b+c) = ab + ac or as a*(b+c) = ab + ac is insubstantial
And neither of those examples is about The Distributive Law - they are both to do with The Distributive Property (and you wrote the first one wrong anyway - it’s a(b+c)=(ab+ac). Premature removal of brackets is how many people end up with the wrong answer).
If I write f^{-1}(x), without context, you have literally no way of knowing whether I am talking about a multiplicative or a functional inverse, which means that it is ambiguous
The inverse of the function is f(x)^-1. i.e. the negative exponent applies to the whole function, not just the x (since f(x) is a single term).
Do you not understand that syntax is its own set of rules?
Yes, the rules of Maths, as I was already saying. I’m a Maths teacher. I take it you didn’t read the link then.
Please learn some math
I’m a Maths teacher - how about you?
Quoting yourself as a source
I wasn’t. I quoted Maths textbooks, and if you read further you’ll find I also quoted historical Maths documents, as well as showed some proofs.
I didn’t say the distributive property, I said The Distributive Law. The Distributive Law isn’t ax(b+c)=ab+ac (2 terms), it’s a(b+c)=(ab+ac) (1 term), but inaccuracies are to be expected, given that’s a wikipedia article and not a Maths textbook.
I did read the answers, try doing that yourself
I see people explaining how it’s not ambiguous. Other people continuing to insist it is ambiguous doesn’t mean it is.
That just states that a*(b + c) = ab + ac
No, The Distributive Law states that a(b+c)=(ab+ac), and that you must expand before you simplify.
For some simple exanples,
Examples by people who simply don’t remember all the rules of Maths. Did you read the answers?
If they weren’t ambiguous, then you wouldn’t see them getting popular
#MathsIsNeverAmbiguous They get popular because people who don’t remember all the rules of Maths want to argue with the people who do remember all the rules of Maths. #DontForgetDistribution
different systems of infix notation
There’s not different rules of Maths though, and the people “debating” the answer are those who don’t remember all the rules.
Those math questions that rely on purposeful ambiguity in order to drive engagement
#MathsIsNeverAmbiguous The engagement is driven by people not remembering the rules of Maths. #DontForgetDistribution
And “Multiplication” refers literally to multiplication signs, of which there are none in this question.
Implicit multiplication is also multiplication
There’s no such thing as implicit multiplication. The answer is 1.
This isn’t really one of the ambiguous ones but it’s fair to consider it unclear.
#MathsIsNeverAmbiguous if you follow all the rules of Maths (there’s a lot of people here who aren’t).
2(4) is not exactly same as 2x4
Correct! It’s exactly the same as (2x4).
if you see a number butted up against an expression in parentheses you assume there is a multiplication symbol there
No, it means it’s a Term (product). If a=2 and b=3, then axb=2x3, but ab=6.
I was taught 2(2+2)==2*(2+2)
2(2+2)==(2*(2+2)). More precisely, The Distributive Law says that 2(2+2)=(2x2+2x2).
Both - see the problem with the logic you use?
Let me know when you decide to consult a textbook about this.