this post was submitted on 12 Dec 2023
857 points (96.4% liked)

Memes

45894 readers
1375 users here now

Rules:

  1. Be civil and nice.
  2. Try not to excessively repost, as a rule of thumb, wait at least 2 months to do it if you have to.

founded 5 years ago
MODERATORS
857
6÷2(1+2) (programming.dev)
submitted 1 year ago* (last edited 1 year ago) by [email protected] to c/[email protected]
 

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 :)

you are viewing a single comment's thread
view the rest of the comments
[–] [email protected] 4 points 1 year ago (2 children)

Damn ragebait posts, it's always the same recycled operation. They could at least spice it up, like the discussion about absolute value. What's |a|b|c|?

What I gather from this, is that Geogebra is superior for not allowing ambiguous notation to be parsed 👌

[–] [email protected] 5 points 1 year ago (2 children)

Your example with the absolute values is actually linked in the "Even more ambiguous math notations" section.

Geogebra has indeed found a good solution but it only works if you input field supports fractions and a lot of calculators (even CAS like WolframAlpha) don't support that.

[–] [email protected] 4 points 1 year ago

Yeah! That's why I mentioned it, it was a fresh ambiguous notation problem that I've never encountered before. Discussions of "is it 1 or 9" get tiring quickly.

At least WA and others tell you how they interpret the input, instead of being a black box (until you get to the manuals). Even though it is obvious in hindsight, I didn't get why two calculators would yield different results; thanks!

Nice write-up.

[–] [email protected] 0 points 9 months ago

Even more ambiguous math notations

Except that isn't ambiguous either. See my reply to the original comment.

Geogebra has indeed found a good solution

Geogebra has done the same thing as Desmos, which is wrong. Desmos USED TO give correct answers, but then they changed it to automatically interpret / as a fraction, which is good, except when they did that it ALSO now interprets ÷ as a fraction, which is wrong. ½ is 1 term, 1÷2 is 2 terms (but Desmos now treats it as 1 term, which goes against the definition of terms)

[–] [email protected] 1 points 9 months ago

What’s |a|b|c|?

The absolute value of a, times b, times the absolute value of c (which would be more naturally written as b|ac|). Unlike brackets, there's no such thing as nested absolute value. If you wanted it to read as the absolute value of (a times the absolute value of b times c), then that's EXACTLY the same answer as the absolute value of (a times b times c), which is why nested absolute values make no sense - you only have to take absolute value once to get rid of all the contained signs.