Comment on I dunno

• JackbyDev@programming.dev ⁨2⁩ ⁨weeks⁩ ago

  They did the joke wrong. To do it right you need to use the ÷ symbol. Because people never use that after they learn fraction, people treat things like a + b ÷ c + d as

  a + b
  -----
  c + d
  

  Or (a + b) ÷ (c + d) when they should be treating it as a + (b ÷ c) + d.

  That’s the most common one of these “troll.math” tricks. Because notating as

  a + b + d
      -
      c
  

  Is much more common and useful. Do people get used to grouping everything around the division operator as if they’re in parentheses.

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  • SmartmanApps@programming.dev ⁨3⁩ ⁨days⁩ ago

    Because people never use that after they learn fractions,

    Yes they do, because not every division is a fraction

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    • JackbyDev@programming.dev ⁨3⁩ ⁨days⁩ ago

      math.berkeley.edu/~wu/order5.pdf

      Image

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      • SmartmanApps@programming.dev ⁨3⁩ ⁨days⁩ ago

        math.berkeley.edu/~wu/order5.pdf

        I already said he was wrong about that. Quoting him saying it doesn’t change that he’s wrong about it

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  • CannonFodder@lemmy.world ⁨2⁩ ⁨weeks⁩ ago

    Or
    12 / 2(6) And trying to argue this is 36.

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    • JackbyDev@programming.dev ⁨2⁩ ⁨weeks⁩ ago

      Now that’s a good troll math thing because it gets really deep into the weeds of mathematical notation. There isn’t one true order of operations that is objectively correct, and in top of that, that’s hardly the way most people would write that. As in, if you wrote that by hand, you wouldn’t use the / symbol. You’d either use ÷ or a proper fraction.

      It’s a good candidate for nerd sniping.

      Personally, I’d call that 36 as written given the context you’re saying it in, instead of calling it 1. But I’d say it’s ambiguous and you should notate in a way to avoid ambiguities. Especially if you’re in the camp of multiplication like a(b) being different from ab and/or a × b.

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      • SmartmanApps@programming.dev ⁨3⁩ ⁨days⁩ ago

        There isn’t one true order of operations that is objectively correct

        Yes there is, as found in Maths textbooks the world over

        that’s hardly the way most people would write that

        Maths textbooks write it that way

        you wouldn’t use the / symbol

        Yes you would.

        You’d either use ÷

        Same same

        It’s a good candidate for nerd sniping.

        Here’s one I prepared earlier to save you the trouble

        I’d call that 36

        And you’d be wrong

        as written given the context you’re saying it in

        The context is Maths, you have to obey the rules of Maths. a(b+c)=(ab+ac), 5(8-5)=(5x8-5x5).

        But I’d say it’s ambiguous

        And you’d be wrong about that too

        you should notate in a way to avoid ambiguities

        It already is notated in a way that avoids all ambiguities!

        Especially if you’re in the camp of multiplication like a(b)

        That’s not Multiplication, it’s Distribution, a(b+c)=(ab+ac), a(b)=(axb).

        being different from ab

        Nope, that’s exactly the same, ab=(axb) by definition

        and/or a × b

        (axb) is most certainly different to axb. 1/ab=1/(axb), 1/axb=b/a

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    • Feathercrown@lemmy.world ⁨2⁩ ⁨weeks⁩ ago

      The P in PEMDAS means to solve everything within parentheses first; there is no “distribution” step or rule that says multiplying without a visible operator other than parentheses comes first. So yes, 36 is valid here. It’s mostly because PEMDAS never shows up in the same context as this sort of multiplication or large fractions

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      • SmartmanApps@programming.dev ⁨3⁩ ⁨days⁩ ago

        The P in PEMDAS means to solve everything within parentheses first

        and without a(b+c)=(ab+ac), now solve (ab+ac)

        there is no “distribution” step or rule

        It’s a LAW of Maths actually, The Distributive Law.

        Image

        that says multiplying without a visible operator

        It’s not “Multiplying”, it’s Distributing, a(b+c)=(ab+ac)

        So yes, 36 is valid here

        No it isn’t. To get 36 you have disobeyed The Distributive Law, thus it is a wrong answer

        It’s mostly because

        people like you try to gaslight others that there’s no such thing as The Distributive Law

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    • MotoAsh@piefed.social ⁨2⁩ ⁨weeks⁩ ago

      Well, now you might be running into syntax issues instead of PEMDAS issues depending on what they’re confused about. If it’s 12 over 2*6, it’s 1. If it’s 12 ÷ 2 x 6, it’s 36.

      A lot of people try a bunch of funky stuff to represent fractions in text form (like mixing spaces and no spaces) when they should just be treating it like a programmer has to, and use parenthesis if it’s a complex fraction in basic text form.

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  • sukhmel@programming.dev ⁨2⁩ ⁨weeks⁩ ago

    Treat a + b/c + d as a + b/(c + d) I can almost understand, I was guilty of doing that in school with multiplication, but auto-parenthesising the first part is really crazy take, imo

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    • SmartmanApps@programming.dev ⁨3⁩ ⁨days⁩ ago

      Treat a + b/c + d as a + b/(c + d)

      No don’t. That rule was changed more than 130 years ago. a+b/c+d=a+(b/c)+d, Division before Addition

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    • JackbyDev@programming.dev ⁨2⁩ ⁨weeks⁩ ago

      That’s a really odd way to parse it.

      a +   b
          -----
          c + b
      

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• Zephorah@discuss.online ⁨2⁩ ⁨weeks⁩ ago

  Alternatively, the poster calculated the wrong answer, thus assuming this guy was wrong.

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• Ghyste@sh.itjust.works ⁨2⁩ ⁨weeks⁩ ago

  Because OP posts garbage to all the meme communities.

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  • DragonTypeWyvern@midwest.social ⁨2⁩ ⁨weeks⁩ ago

    This shit take got deleted right in front of my eyes

    The system works

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  • SSUPII@sopuli.xyz ⁨2⁩ ⁨weeks⁩ ago

    Oh so just like me on !lemmyshitpost@lemmy.world

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• pixeltree@lemmy.blahaj.zone ⁨2⁩ ⁨weeks⁩ ago

  Gotcha gotcha, sorry

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