this post was submitted on 12 Dec 2023
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submitted 11 months ago* (last edited 11 months ago) by wischi@programming.dev to c/memes@lemmy.ml
 

https://zeta.one/viral-math/

I wrote a (very long) blog post about those viral math problems and am looking for feedback, especially from people who are not convinced that the problem is ambiguous.

It's about a 30min read so thank you in advance if you really take the time to read it, but I think it's worth it if you joined such discussions in the past, but I'm probably biased because I wrote it :)

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[–] SmartmanApps@programming.dev 0 points 9 months ago (1 children)

there’s a mutual agreement that it’s only approximately correct.

No there isn't. I've never seen a single Year 7-8 Maths textbook that is in the slightest bit ambiguous about it. The Distributive Law has to literally always be applied (hence why it's a law). dotnet.social/@SmartmanApps/110819283738912144

[–] kogasa@programming.dev 0 points 9 months ago (1 children)

The order of operations is not the same as the distributive law.

[–] SmartmanApps@programming.dev 0 points 8 months ago (1 children)

The first step in order of operations is solve brackets. The first step in solving unexpanded brackets is to expand them. i.e. The Distributive Law. i.e. the ONLY time The Distributive Law ISN'T part of order of operations is when there's no unexpanded brackets in the expression.

[–] kogasa@programming.dev 1 points 8 months ago (1 children)

The distributive law has nothing to do with brackets.

The distributive law can be written in PEMDAS as a(b+c) = ab + ac, or PEASMD as ab+c = (ab)+(ac). It has no relation to the notation in which it is expressed, and brackets are purely notational.

[–] SmartmanApps@programming.dev -1 points 8 months ago (1 children)

The distributive law has nothing to do with brackets

BWAHAHAHA! Ok then, what EXACTLY does it relate to, if not brackets? Note that I'm talking about The Distributive LAW - which is about expanding brackets - not the Distributive PROPERTY.

a(b+c) = ab + ac

a(b+c)=(ab+ac) actually - that's one of the common mistakes that people are making. You can't remove brackets unless there's only 1 term left inside, and ab+ac is 2 terms.

ab+c = (ab)+(ac)

No, never. ab+c is 2 terms with no further simplification possible. From there all that's left is addition (once you know what ab and c are equal to).

brackets are purely notational

Yep, they're a grouping symbol. Terms are separated by operators and joined by grouping symbols.

[–] kogasa@programming.dev 1 points 8 months ago (1 children)
[–] SmartmanApps@programming.dev 0 points 8 months ago (1 children)

Noted that you were unable to tell me what The Distributive Law relates to (given your claim it's not brackets).

[–] kogasa@programming.dev 0 points 8 months ago

You are unhinged