• then_three_more@lemmy.world
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    9 days ago

    There’s just 5 lots of 2. If it’s hard then think of x being just a bunch of + smooshed together. So

    2 + 2 x 4

    expands to

    2 + 2 + 2 + 2 + 2

    or contracts to

    5 x 2

    • FishFace@piefed.social
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      9 days ago

      You’ve completely not understood that order of operations is an arbitrary convention. How did you decide to expand the definition of multiplication before evaluating the addition? Convention.

      You can’t write 2 + 2 ÷ 2 like this, so how are you gonna decide whether to decide to divide or add first?

      • You’ve completely not understood that order of operations is an arbitrary convention

        No, you’ve completely not understood that they are universal rules of Maths

        How did you decide to expand the definition of multiplication before evaluating the addition? Convention

        The definition of Multiplication as being repeated addition

        You can’t write 2 + 2 ÷ 2 like this

        Yes you can

        so how are you gonna decide whether to decide to divide or add first?

        The rules of Maths, which says Division must be before Addition

        • FishFace@piefed.social
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          11 hours ago

          How are you gonna write 2 + 2 ÷ 2 with repeated addition?

          The definition of Multiplication as being repeated addition

          That doesn’t mean it has to be expanded first. You could expand 2 + 2 × 3 as (2+2)+(2+2)+(2+2) and you are unable to tell me what mathematical law prohibits it.

          If this were a universal law, reverse polish notation wouldn’t work as it does. In RPL, 2 2 + 3 × is 12 but 2 3 × 2 + is 8. If you had to expand multiplication first, how would it work? The same can be done with prefix notation, and the same can be done with “pre-school” order of operations.

          Different programming languages have different orders of operations, and those languages work just fine.

          Your argument amounts to saying that it makes the most sense to do multiplication before addition. Which is true, but that only gives you a convention, not a rule.