• Alaknár@sopuli.xyz
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    18 days ago

    Division, Multiplication, Addition, and Subtraction

    This is fucking so many people over… It should be limited - like Orders - to only Multiplication and Addition.

    Because division is the same operation as multiplication, and subtraction is the same operation as addition, and they have the same “weight” in the order of operations (meaning, you do them left-to-right).

    • It should be limited - like Orders - to only Multiplication and Addition

      Because you don’t want people to know when to do Division and Subtraction? 😂

      Because division is the same operation as multiplication

      No it isn’t, but they are both binary operators.

      they have the same “weight” in the order of operations (meaning, you do them left-to-right)

      And where are they going to do Division and Subtraction in the left to right if you’ve left them out? 🙄

      • Alaknár@sopuli.xyz
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        1 day ago

        Because you don’t want people to know when to do Division and Subtraction? 😂

        Because division is multiplication, and subtraction is addition.

        No it isn’t, but they are both binary operators.

        2/2 is the same as 2*½

        2-2 is the same as 2+(-2)

        And where are they going to do Division and Subtraction in the left to right if you’ve left them out? 🙄

        Well, as I already said multiple times: Division = Multiplication and Subtraction = Addition, therefore they would be doing them together, left to right. As in: 9-3+2 would not confuse anyone who learned “Addition → Subtraction”, as it does right now.

        • Because division is multiplication

          No it isn’t.

          and subtraction is addition

          And you still have to do both

          2/2 is the same as 2*½

          They’re equal in value, they’re not the same

          2-2 is the same as 2+(-2)

          You got that the wrong way around. Brackets have only been used in Maths for a few centuries now

          Well, as I already said multiple times: Division = Multiplication

          And you were wrong every time you said it.

          therefore they would be doing them together

          Not if you left them out of the mnemonic and they didn’t know when to do them

          • Alaknár@sopuli.xyz
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            18 hours ago

            No it isn’t.

            Yes, it is.

            And you still have to do both

            Quote the part where I said you didn’t.

            They’re equal in value, they’re not the same

            They are the same.

            You got that the wrong way around. Brackets have only been used in Maths for a few centuries now

            1. How is that “having it the wrong way around”?
            2. What does that have to do with the topic at hand? We’re talking about maths today, not centuries ago.

            And you were wrong every time you said it.

            No, they’re not.

            Not if you left them out of the mnemonic and they didn’t know when to do them

            Mnemonic without understanding what you’re doing doesn’t help. Which is why people get confused and argue online that you must do addition before subtraction, or the other way around, depending on what the mnemonic they learned was.

            Understanding that subtraction is just the addition of a negative number solves this problem.

            • Yes, it is

              No it isn’t 😂

              Quote the part where I said you didn’t.

              The part where you said to leave it out of the mnemonic “It should be limited - like Orders - to only Multiplication and Addition”

              They are the same.

              Nope. 2/2 is not the same as 2*½. Do you need glasses or something??

              How is that “having it the wrong way around”?

              Because 2-2 came first, before we started using Brackets in Maths, by several hundred years

              What does that have to do with the topic at hand?

              You glibly ignoring the history and rules of Maths 🙄

              No, they’re not

              Still wrong 😂

              Mnemonic without understanding what you’re doing

              That’s EXACTLY what the mnemonics are for! 😂 Don’t need to understand it, just follow the steps

              Which is why people get confused and argue online that you must do addition before subtraction

              No-one gets confused or angry about that. 😂 There are textbooks that specifically teach to do it that way

              or the other way around, depending on what the mnemonic they learned was

              I have never seen any textbook say to do Subtraction before Addition, everyone is taught Addition first

              Understanding that subtraction is just the addition of a negative number solves this problem

              Understanding that you can do them in any order proves there is no problem 😂

              • Alaknár@sopuli.xyz
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                13 hours ago

                No it isn’t 😂

                Yes it is.

                The part where you said to leave it out of the mnemonic “It should be limited - like Orders - to only Multiplication and Addition”

                If you understand what is multiplication and what is addition, then you know what this doesn’t suggest ignoring division or subtraction at all.

                Nope. 2/2 is not the same as 2*½. Do you need glasses or something??

                OK, teach me. What’s the result of 2/2 and what’s the result of 2*½?

                Because 2-2 came first, before we started using Brackets in Maths, by several hundred years

                Explain how is that relevant to the discussion. Or to the example I gave, where brackets are only used for readability sake, they’re not changing the results in any way. You might as well note that as -2+2 - see? No scary brackets anymore, same result.

                You glibly ignoring the history and rules of Maths 🙄

                Well… yes, because we’re not talking about the history, we’re talking about the current rules.

                That’s EXACTLY what the mnemonics are for! 😂 Don’t need to understand it, just follow the steps

                This whole thread stemmed from the fact that some people were taught PEMDAS while others where taught PEDMAS.

                Are you suggesting that the order of operations depends on your maths teacher?

                No-one gets confused or angry about that

                Wow, let me be the first to welcome you to the Internet! I know it might be jarring at first, but give it time and you’ll get used to the weirdness! Glad to see you joining!

                There are textbooks that specifically teach to do it that way

                Great! Now find one that actually talks about that, instead of one that talks about the addition of similar monomials, which is a different thing altogether.

                Actually, you know what? Never mind - instead just read the part you posted, but slower. Here, let me highlight the important bit:

                Addition of similar monomials is performed by taking the arithmetical difference between the total of the positive and the total of the negative coefficients, giving it the sign of the numerically greater total, and annexing it to the common literal part”

                Which actually reinforces my point.

                I have never seen any textbook say to do Subtraction before Addition, everyone is taught Addition first

                See? This is exactly what I was talking about. Addition is NOT first, unless it’s the first on the right. If subtraction is first, you do subtraction first.

                Understanding that you can do them in any order proves there is no problem 😂

                Again, let me extend a warm welcome on behalf of everyone on the Internet. I believe you’ll have a great time here.

                • mindbleach@sh.itjust.works
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                  4 hours ago

                  This guy thinks 3(2+1) gets the wrong answer if you do 3(3) instead of 3*2+3*1. They will never learn anything and they will never shut up about it. This trolling bullshit is the only thing I’ve ever seen them comment.

                  Proceed apace if slapping that down entertains you - but proceed knowing it’s all you’re going to get.

                  • Alaknár@sopuli.xyz
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                    4 hours ago

                    Oh, I realised that a long ago, but it’s actually a kind of “mental exercise” for me. :) Cheers!

                • Yes it is

                  You can say that as much as you want and you’ll still be just as wrong. Noted that, yet again, you are unable to cite any Maths textbooks that agree with you

                  If you understand what is multiplication and what is addition

                  Again, the mnemonics are for people who don’t understand, which would be people like you! 😂

                  What’s the result of 2/2 and what’s the result of 2*½

                  What’s the result of 2+2? What’s the result of 1+3? Are 2+2 and 1+3 the same? No! 😂 2 apples + 2 oranges = 4 pieces of fruit. 3 apples and 1 orange = 4 pieces of fruit. Is 2 apples and 2 oranges the same as 3 apples and 1 orange? 😂 Anything else you want to embarrass yourself about not understanding?

                  Explain how is that relevant to the discussion

                  You’re the one who brought it into the conversation - you tell me! 😂

                  where brackets are only used for readability sake

                  You’ll find most people find that less readable. Welcome to why textbooks never use them

                  they’re not changing the results in any way

                  Just making it less readable.

                  Well… yes, because we’re not talking about the history

                  You are when you start dragging brackets into something that never used brackets for hundreds of years

                  we’re talking about the current rules

                  which haven’t changed at all in all that time 😂 2-3 has never and still does not require brackets, same as when Arithmetic was first written.

                  This whole thread stemmed from the fact that some people were taught PEMDAS while others where taught PEDMAS.

                  and everyone was taught that the order of DM/MD does not matter. If it did then one of them would not exist

                  Are you suggesting that the order of operations depends on your maths teacher?

                  No! You might want to work on your comprehension as well 😂

                  Wow, let me be the first to welcome you to the Internet!

                  Been here longer than you probably, and know full well what you said is a lie 😂

                  Now find one that actually talks about that

                  Already posted a screenshot of one. You really need to work on your comprehension

                  the addition of similar monomials, which is a different thing altogether

                  Set all the pronumerals to 1, and guess what you have - the exact same thing 😂 I see you don’t understand how pronumerals work either

                  BTW you still have not cited any textbook whatsoever that agrees with anything that you have said, in case you needed that reminder 😂

                  instead just read the part you posted, but slower.

                  says person who doesn’t understand that pronumerals can equal 1. 🙄

                  the arithmetical difference between the total of the positive and the total of the negative coefficients,

                  Yep, 1a-2a+3a-4a=a((1+3)-(2+4)). Now set a=1 and guess what you have? 😂

                  giving it the sign of the numerically greater total, and annexing it to the common literal part

                  You telling me you don’t understand what that means? +4-2=+2. +2-4=-2. Not complicated

                  Which actually

                  proves you’re wrong 😂

                  Addition is NOT first

                  You know the textbook just literally told you it is, right?? 😂

                  unless it’s the first on the right

                  It’s first regardless of where it is. Did the textbook says it depends on where it is? No 😂

                  Again, let me extend a warm welcome on behalf of everyone on the Internet

                  Where nearly half of adults have forgotten the rules of Maths, and everyone else knows there is no problem 😂

                  • Alaknár@sopuli.xyz
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                    3 hours ago

                    You can say that as much as you want and you’ll still be just as wrong.

                    That’s the thing - I’m not wrong.

                    Noted that, yet again, you are unable to cite any Maths textbooks that agree with you

                    Yet again? You never asked for citations. I also didn’t have to, as you did it for me with your screenshot.

                    But here you go:

                    In mathematics, a multiplicative inverse or reciprocal for a number x, denoted by 1/x or x−1, is a number which when multiplied by x yields the multiplicative identity, 1. The multiplicative inverse of a fraction a/b is b/a. Dividing 1 by a real number yields its multiplicative inverse. For example, the reciprocal of 5 is one fifth (1/5 or 0.2) (…) Multiplying by a number is the same as dividing by its reciprocal and vice versa.

                    Here’s another [source] if you’re allergic to Wikipedia.

                    Again, the mnemonics are for people who don’t understand, which would be people like you! 😂

                    Again, the mnemonics, when taught without appropriate context, cause confusion in people like you, who think that the order of operations is set to: Multiplication → Division → Addition → Subtraction, instead of being (M or D, start from the left) → (A or S, start from the left).

                    Again, the mnemonics, when taught without appropriate context, cause people to think that 9-3+2 is 4, when the actual result is 8, because they think that they have to calculate the addition first.

                    What’s the result of 2+2? What’s the result of 1+3? Are 2+2 and 1+3 the same? No! 😂 2 apples + 2 oranges = 4 pieces of fruit. 3 apples and 1 orange = 4 pieces of fruit. Is 2 apples and 2 oranges the same as 3 apples and 1 orange? 😂 Anything else you want to embarrass yourself about not understanding?

                    WTF are you talking about? Where did you get the 1 and 3 from? Also… Do you not know what fractions are…?

                    You’re the one who brought it into the conversation - you tell me!

                    You’re so very, very confused by all of this…

                    You’ll find most people find that less readable. Welcome to why textbooks never use them

                    I can see why you are finding them less readable - you have absolutely fundamental lacks in understanding of maths. And, sorry to burst your bubble, but maths textbooks all over the world use brackets all the time.

                    Just making it less readable

                    Not if you understand what they mean. Which is why they’re confusing for you, I guess.

                    which haven’t changed at all in all that time 😂 2-3 has never and still does not require brackets, same as when Arithmetic was first written.

                    Now that I know that you have a fundamental lack of understanding how maths works, I apologise for using the brackets earlier. Let’s try this: you can write 2 - 2 as -2 + 2, or - a slightly less legible version - as 2 + -2. You’ll get the same result, and this inversion is a perfectly “legal” mathematical operation. Which shows you how addition and subtraction are equal.

                    and everyone was taught that the order of DM/MD does not matter. If it did then one of them would not exist

                    One more time, let me welcome you to the Internet, I’m sure you’ll have a great time here!

                    Already posted a screenshot of one. You really need to work on your comprehension

                    We were not talking about monomials.

                    Set all the pronumerals to 1, and guess what you have - the exact same thing 😂 I see you don’t understand how pronumerals work either

                    If you set the pronumerals in addition/subtraction problems to 1, you would have something entirely different. And if you want to do 2x - 2x where x = 1, then your own posted fragment explains that you only need to calculate the arithmetic difference between the total postive/negative coefficients.

                    The arithmetic difference between -2 + 2 and 2 - 2 is the same, proving - again - that subtraction is equal to addition of a negative.

                    Which is my point. Which you are proving.

                    BTW you still have not cited any textbook whatsoever that agrees with anything that you have said

                    I didn’t have to, you did it for me.

                    Yep, 1a-2a+3a-4a=a((1+3)-(2+4)). Now set a=1 and guess what you have? 😂

                    Now do -(2+4) + (1+3) and guess what you have?

                    You know the textbook just literally told you it is, right?? 😂

                    I already suggested this: read it again, but slower.