this post was submitted on 31 May 2025
242 points (100.0% liked)

Technology

71923 readers
3146 users here now

This is a most excellent place for technology news and articles.

Our Rules

  1. Follow the lemmy.world rules.
  2. Only tech related news or articles.
  3. Be excellent to each other!
  4. Mod approved content bots can post up to 10 articles per day.
  5. Threads asking for personal tech support may be deleted.
  6. Politics threads may be removed.
  7. No memes allowed as posts, OK to post as comments.
  8. Only approved bots from the list below, this includes using AI responses and summaries. To ask if your bot can be added please contact a mod.
  9. Check for duplicates before posting, duplicates may be removed
  10. Accounts 7 days and younger will have their posts automatically removed.

Approved Bots

founded 2 years ago
MODERATORS
[email protected]
[email protected]
[email protected]
[email protected]
[email protected]
[email protected]
242
A fake Facebook event disguised as a math problem has been one of its top posts for 6 months (www.engadget.com)
submitted 3 weeks ago by [email protected] to c/[email protected]
142 comments fedilink hide all child comments
you are viewing a single comment's thread
view the rest of the comments
[–] [email protected] 3 points 3 weeks ago* (last edited 3 weeks ago) (2 children)

Those two things are memorisation tasks. Maths is not about memorisation.

You are not supposed to remember that the area of a triangle is a * h / 2, you're supposed to understand why it's the case. You're supposed to be able to show that any triangle that can possibly exist is half the area of the rectangle it's stuck in: Start with the trivial case (right-angled triangle), then move on to more complicated cases. If you've understood that once, there is no reason to remember anything because you can derive the formula at a moment's notice.

All maths can be understood and derived like that. The names of the colours, their ordering, the names of the planets and how they're ordered, they're arbitrary, they have no rhyme or reason, they need to be memorised if you want to recall them. Maths doesn't, instead it dies when you apply memorisation.

Ein Anfänger (der) Gitarre Hat Elan. There, that's the Guitar strings in German. Why do I know that? Because my music theory knowledge sucks. I can't apply it, music is all vibes to me but I still need a way to match the strings to what the tuner is displaying. You should never learn music theory from me, just as you shouldn't learn maths from a teacher who can't prove a * h / 2, or thinks it's unimportant whether you can prove it.

[–] [email protected] 1 points 7 hours ago

Maths is not about memorisation

It is for ROTE learners.

You are not supposed to remember that the area of a triangle is a * h / 2

Yes you are. A lot of students get the wrong answer when they forget the half.

you’re supposed to understand why it’s the case

Constructivist learners can do so, ROTE learners it doesn't matter. As long as they all know how to do Maths it doesn't matter if they understand it or not.

You’re supposed to be able to show that any triangle that can possibly exist is half the area of the rectangle it’s stuck in

No they're not.

If you’ve understood that once, there is no reason to remember anything because you can derive the formula at a moment’s notice.

And if you haven't understood it then there is a reason to remember it.

you can derive the formula at a moment’s notice

Students aren't expected to be able to do that.

All maths can be understood and derived like that

It can be by Constructivist learners, not ROTE learners.

The names of the colours, their ordering, the names of the planets and how they’re ordered, they’re arbitrary

No they're not. Colours are in spectrum order, the planets are in order from the sun.

Maths doesn’t, instead it dies when you apply memorisation

A very substantial chunk of the population does just fine with having memorised Maths.

[–] [email protected] 4 points 3 weeks ago (2 children)

What fundamental property of the universe says that

6 + 4 / 2 is 8 instead of 5?

[–] [email protected] 1 points 7 hours ago (1 children)

6 + 4 / 2 is 8 instead of 5?

The fundamental property of Maths that you have to solve binary operators before unary operators or you end up with wrong answers.

[–] [email protected] 1 points 4 hours ago* (last edited 3 hours ago)

But +, -, *, and / are all binary operators?

As far as I know, the only reason multiplication and division come first is that we've all agreed to it. But it can't be derived in a vacuum as that other dude contends it should be.

[–] [email protected] 4 points 3 weeks ago* (last edited 3 weeks ago) (1 children)

Nothing. And that's why people don't write equations like that: You either see

     4
6 +
***
     2

or

 6 + 4
-------
   2

If you wrote 6 + 4 / 2 in a paper you'd get reviewers complaining that it's ambiguous, if you want it to be on one line write (6+4) / 2 or 6 + (4/2) or 6 + ⁴⁄₂ or even ½(6 + 4) Working mathematicians never came up with PEMDAS, which disambiguates it without parenthesis, US teachers did. Noone else does it that way because it does not, in the slightest, aid readability.

[–] [email protected] 2 points 7 hours ago* (last edited 7 hours ago)

And that’s why people don’t write equations like that

Says someone who clearly hasn't looked in any Maths textbooks

If you wrote 6 + 4 / 2 in a paper you’d get reviewers complaining that it’s ambiguous

Only if their Maths was very poor. #MathsIsNeverAmbiguous

Working mathematicians never came up with PEMDAS

Yes they did.

which disambiguates it without parenthesis

It was never ambiguous to begin with.

Noone else does it that way

Says someone who has never looked in a non-U.S. Maths textbooks - BIDMAS, BODMAS, BEDMAS, all textbooks have one variation or another.