• AbidanYre@lemmy.world
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        22 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.

        • 💡𝚂𝗆𝖺𝗋𝗍𝗆𝖺𝗇 𝙰𝗉𝗉𝗌📱@programming.dev
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          15 hours ago

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

          No, only multiply and divide are. 2+3 is really +2+3, but we don’t write the first plus usually (on the other hand we do always write the minus if it starts with one).

          As far as I know, the only reason multiplication and division come first is that we’ve all agreed to it.

          No, they come first because you get wrong answers if you don’t do them first. e.g. 2+3x4=14, not 20. All the rules of Maths exist to make sure you get correct answers. Multiplication is defined as repeated addition - 3x4=3+3+3+3 - hence wrong answers if you do the addition first (just changed the multiplicand, and hence the answer). Ditto for exponents, which are defined as repeated multiplication, a^2=(axa). Order of operations is the process of reducing everything down to adds and subtracts on a number line. 3^2=3x3=3+3+3

            • Very confidently getting basic facts wrong doesn’t inspire confidence in the rest of your comments.

              …says person quoting Wikipedia and NOT a Maths textbook! 😂

              Your example still doesn’t give a reason why 2 + 3 * 4 is 2 + 3 + 3 + 3 +3

              Yes it does., need to work on your comprehension…

              Multiplication is defined as repeated addition - 3x4=3+3+3+3

              other than that we all agree to it

              You can disagree as much as you want and 3x4 will still be defined as 3+3+3+3. It’s been that way ever since Multiplication was invented.

              • AbidanYre@lemmy.world
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                11 hours ago

                The arithmetic operations, addition + , subtraction − , multiplication × , and division ÷

                That better? Or you can find one you like all by yourself: https://duckduckgo.com/?q=binary+operator&ko=-1&ia=web

                Yes it does., need to work on your comprehension…

                And you can shove the condescension up your ass until you understand the difference between unary and binary operators.

                But to original point. I’m not disagreeing with anything and you’re proving my point for me. There is no fundamental law of the universe that says multiplication comes first. It’s defined by man and agreed to. If we encounter aliens someday, the area of their triangles are still going to be half the width times the height, the ratios of their circles circumference to diameter are still going to be pi, regardless of how they represent those values. But they could very well prioritize addition and subtraction over multiplication and division.

                • That better?

                  Is it a Maths textbook?

                  Or you can find one you like all by yourself

                  I already have dozens of Maths textbooks thanks.

                  And you can shove the condescension up your ass until you understand the difference between unary and binary operators

                  It’s not me who doesn’t understand the difference.

                  you’re proving my point for me.

                  Still need to work on your comprehension then. I did nothing of the sort.

                  There is no fundamental law of the universe that says multiplication comes first.

                  Yes there is. The fact that it’s defined as repeated addition. You don’t do it first, you get wrong answers.

                  It’s defined by man and agreed to

                  It’s been defined and man has no choice but to agree with the consequences of the definition, or you get wrong answers.

                  But they could very well prioritize addition and subtraction over multiplication and division

                  No they couldn’t. It gives wrong answers.

                  • AbidanYre@lemmy.world
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                    11 hours ago

                    Actually, it is. Written by a PhD and used in a college course. It just happens to be distributed for free because Canada is cool like that.

                    The LibreTexts libraries are Powered by NICE CXone Expert and are supported by the Department of Education Open Textbook Pilot Project, the UC Davis Office of the Provost, the UC Davis Library, the California State University Affordable Learning Solutions Program

                    May want to work on your own reading comprehension.

                    It’s not me who doesn’t understand the difference.

                    The facts disagree.

                    You can keep saying defined all you want, it doesn’t change the underlying issue that it’s defined by man. In the absence of all your books (which you clearly don’t understand anyway based on our discussion of unary vs binary) order of operations only exists because we all agree to it.

    • barsoap@lemm.ee
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      28 days ago

      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.

      • 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.