• If you can simplify before distributing - and the PDFs you spam say you can

    They say you can do that when there is Addition or Subtraction inside the Brackets. They also say you cannot Distribute over Multiplication, at all

    then there is no difference

    There is no difference between Addition and Multiplication?? 😂

    You made it the fuck up

    And yet, there it is in textbooks that were written before I was even born 😂

    2(n)2 is 2n2 whether n=a+b or n=a*b=ab

    Nope! a(b+c)=(ab+ac). a(bxc)=abc

    If you want to square the 2, that’s (2n)2.

    or 2²xn², or 2(½n+½n)²

    It’s not about the multiply sign, or grouping, or division

    Yes it is! 😂 If there’s a Multiply or a Divide, you cannot Distribute.

    You fooled yourself into saying 2=1

    Not me! 😂

    • mindbleach@sh.itjust.works
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      4 days ago

      Every textbook with an answer key says you’re full of shit.

      Physical calculators say you’re full of shit.

      Advanced math programs say you’re full of shit.

      You can keep talking, but you’re obviously just full of shit.

      At some point you’re either so deep in denial you should speak Swahili, or else being wrong on purpose is the point. The answer in either case is shut the fuck up.

      2(n)2 is 2n2. Anything else is an inane complication nobody else believes in or uses or needs.

      • Every textbook with an answer key says you’re full of shit

        Says person who can’t find a Maths textbook that says a(bxc)=(abxac) 🙄

        being wrong on purpose is the point

        I’m gonna presume that’s why you keep claiming a(bxc)=(abxac) 🙄

        The answer in either case is shut the fuck up

        says person still not doing that 😂

        2(n)2 is 2n2

        No it isn’t! 😂 2xn² is

        Anything else is an inane complication nobody else believes in or uses or needs

        Except for authors of Maths textbooks 😂

            • FishFace@piefed.social
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              2 days ago

              An algebraic expression written as a product or quotient of numerals or variables or both is called a term

              So b * c, which is a product of the variables b and c, is a term, according to this textbook.

              You seem to be getting confused because none of the examples on this particular page feature the multiplication symbol ×. But that is because on the previous page, the author writes:

              When a product involves a variable it is customary to omit the symbol × of multiplication.

              That means that the expression bc is just another way of writing b×c; it is treated the same other than requiring fewer strokes of the pen or presses on a keyboard, because this is just a custom. That should clear up your confusion in interpreting this textbook (though really, the language is clear: you don’t dispute that b×c - or b * c - are products, do you.)

              Elsewhere in this thread you are clearly confused about what brackets mean. They are explained on page 20 of your textbook, where it says that you evaluate the expression inside the (innermost) brackets before doing anything else. Notice that, in its elucidation of several examples, involving addition and multiplication, the “distributive law” is not mentioned, because the distributive law has nothing to do with brackets and is not an operation.

              Thus the expression 3 × (2 + 4) can be evaluated by first performing the summation inside the brackets to get 3 × 6 and then the product to get 18. The textbook then says that it is customary to omit the multiplication symbol and instead write 3(2+4), again indicating that these expressions are merely different ways of writing the same thing.

              The exact same process of course must be followed whether numbers are represented by numerals or by letters designating a variable. You cannot do algebra if you don’t follow the same procedure in both cases. So consider the expression 2(a+b)². You have suggested that you must evaluate this as (2a+2b)² because you must “do brackets first”, but this is not what “doing brackets” means. You haven’t produced any authority to suggest that it is, and your own textbook makes it clear that “doing brackets” means do what is inside the brackets first. Not what is outside the brackets. Distributing 2 over a+b is not “doing brackets”; it is multiplication and comes afterwards.

              If 2(a+b)² were equal to (2a+2b)² let us try with a=b=2. Let us first evaluate (2a+2b)²: it is equal to (2×2+2×2)² = (4+4)² = 8² = 64. Now let us evaluate 2(a+b)²: it is 2(2+2)² and now, following your textbook’s instruction to do what is inside the brackets first, this is equal to 2(4)². The next highest-priority operation is the exponent, giving us 2×16 (we now must write the × because it is an expression purely in numerals, with no brackets or variables) which is 32.

              The fact that these two answers are different is because your understandings of what it means to “do brackets” and the distributive law are wrong.

              Since I’m working off the textbook you gave, and I referred liberally to things in that textbook, I’m sure if you still disagree you will be able to back up your interpretations with reference to it.

              By the way, I noticed this statement on page 23, regarding the order of operations:

              However, mathematicians have agreed on a rule to fall back on if someone omits punctuation marks.

              it does rather seem like this rule is one established not by the fundamental laws of mathematics but by agreement as they say, does it not? Care to comment?

              • So b * c, which is a product of the variables b and c

                Nope. bc is the product of b and c. bxc is Multiplication of the 2 Terms b and c.

                according to this textbook

                Says person who clearly didn’t read more than 2 sentences out of it 🙄

                none of the examples on this particular page feature the multiplication symbol ×

                and why do you think that is? Do explain. We’re all waiting 😂 Spoiler alert: if you had read more than 2 sentences you would know why

                That means that the expression bc is just another way of writing b×c;

                No it doesn’t. it means bxc is Multiplication, and bc is the product 🙄 Again you would’ve already known this is you had read more than 2 sentences of the book.

                it is treated the same other than requiring fewer strokes of the pen

                No it isn’t, and again you would already know this if you had read more than 2 sentences. If a=2 and b=3, then…

                1/ab=1/(2x3)=1/6

                1/axb=1/2x3=3/2

                this is just a custom

                Nope, an actual rule of Maths. If you meant 1/axb, but wrote 1/ab, you’ve gonna get a different answer 🙄

                That should clear up your confusion in interpreting this textbook

                says person who only read 2 sentences out of it 🙄

                though really, the language is clear:

                It sure is when the read the rest of the page 🙄

                you don’t dispute that b×c - or b * c - are products, do you

                What don’t you understand about only ab is the product of a and b?

                Elsewhere in this thread you are clearly confused about what brackets mean

                Not me, must be you! 😂

                They are explained on page 20 of your textbook, where it says that you evaluate the expression inside the (innermost) brackets before doing anything else.

                Until all brackets have been removed. on the very next page. 🙄 See what happens when you read more than 2 sentences out of a textbook? Who would’ve thought you need to read more than 2 sentences! 😂

                the “distributive law” is not mentioned, because the distributive law has nothing to do with brackets

                And yet, right there on Page 21, they Distribute in the last step of removing Brackets, 🙄 5(17)=85, and throughout the whole rest of the book they write Products in that form, a(b) (or just ab as the case may be).

                is not an operation

                Brackets aren’t an operator, they are grouping symbols, and solving grouping symbols is done in the first 2 steps of order of operations, then we solve the operators.

                Thus the expression 3 × (2 + 4) can be evaluated by first performing the summation inside the brackets to get 3 × 6 and then the product to get 1

                3x6 isn’t a Product, it’s a Multiplication, done in the Multiplication step of order of operations.

                The textbook then says that it is customary to omit the multiplication symbol and instead write 3(2+4)

                It says you omit the multiplication sign if it’s a Product, and 3x6 is not a Product. I’m not sure how many times you need to be told that 🙄

                again indicating that these expressions are merely different ways of writing the same thing

                Nope, completely different giving different answers

                1/3x(2+4)=1/3x6=6/3=2

                1/3(2+4)=1/3(6)=1/18

                You have suggested that you must evaluate this as (2a+2b)² because you must “do brackets first”

                Yep

                this is not what “doing brackets” means.

                Yes it is! 😂

                Not what is outside the brackets.

                Yes it is! 😂 Until all Brackets have been removed, which they can’t be if you haven’t Distributed yet. Again, last step of the working out…

                Distributing 2 over a+b is not “doing brackets”;

                Yes it is! 😂 Until all Brackets have been removed

                it is multiplication and comes afterwards

                Nope, it’s Distribution, done in the Brackets step, before doing anything else, as per Page 21

                following your textbook’s instruction to do what is inside the brackets first, this is equal to 2(4)²

                Which, when you finish doing the brackets, is 8²

                The next highest-priority operation is the exponent

                After you have finished the Brackets 🙄

                giving us 2×16

                Nope. Giving us 8²=64

                we now must write the × because it is an expression purely in numerals

                Nope! If you write it at all, which you don’t actually need to (the textbook never does), then you write (2x4)², per The Distributive Law, where you cannot remove the brackets if you haven’t Distributed yet. There’s no such rule as the one you just made up

                The fact that these two answers are different is because

                You disobeyed The Distributive Law in the second case, and the fact that you got a different answer should’ve been a clue to you that you did it wrong 🙄

                what it means to “do brackets” and the distributive law are wrong

                No, that would be your understanding is wrong, the person who only read 2 sentences 🙄 I’m not sure what you think the rest of the chapter is about.

                Since I’m working off the textbook you gave

                Says person who only read 2 sentences out of it 🙄

                I referred liberally to things in that textbook

                Yep, ignoring all the parts that prove you are wrong 🙄

                I’m sure if you still disagree you will be able to back up your interpretations with reference to it

                Exact same reference! 😂

                it does rather seem like this rule is one established not by the fundamental laws of mathematics but by agreement as they say

                You know Mathematicians tend to agree when something has been proven, right? 😂

                Care to comment?

                Yep, read the whole chapter 🙄

                • FishFace@piefed.social
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                  7 hours ago

                  Do you teach classes like this? “That’s not a product, it’s a multiplication” – those are the same thing. Shouldn’t you, as a teacher, be explaining the difference, if you say there is one? I’m starting to believe you don’t think they’re is one, but are just using words to be annoying. Or maybe you don’t explain because you don’t know.

                  You could argue that “product” refers to the result of the multiplication rather than the operation, but there’s no sense in which the formula “a × b” does not refer to the result of multiplying a and b.

                  Of course, you don’t bother to even make such an argument because either that would make it easier to see your trolling for what it is, or you’re not actuality smart enough to understand the words you’re using.

                  It’s interesting, isn’t it, that you never provide any reference to your textbooks to back up these strange interpretations. Where in your textbook does it say explicitly that ab is not a multiplication, or that a multiplication is different from a product in any substantive sense, eh? It doesn’t, does it? You’re keen to cite textbooks any time you can, but here you can’t. You complain that people don’t read enough of the textbook, yet they read more than you ever refer to.

                  In the other thread I said I wouldn’t continue unless you demonstrated your good faith by admitting to a simple verifiable fact that you got wrong. Here’s another option: provide an actual textbook example where any of the disputed claims you make are explicitly made. For example, there should be some textbook somewhere which says that mathematics would not work with different orders of operations - you’ve never found a textbook which says anything like this, only things like “mathematicians have agreed” (and by the way, hilarious that you commit the logical fallacy of affirming the consequent on that one).

                  Likewise with your idea of what constitutes a term, where’s your textbook which says that “a × b is not a term”? Where is the textbook that says 5(17) requires distribution? (All references you have given are that distribution relates multiplication and addition, but there’s no addition) Where’s your textbook which says “ab is a product, not multiplication”? Where’s a citation saying “product is not the same as multiplication and here’s how”? Because there is a textbook reference saying “ab means the same as a × b”, so your mental contortions are not more authoritative.

                  Find any one of these - explicitly, not implicitly, (because your ability to interpret maths textbooks is poor) and we can have a productive discussion, otherwise we cannot.

                  My prediction: you’ll present some implicit references and try to argue they mean what you want. In that case, my reply is already prepared 😁

                • mindbleach@sh.itjust.works
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                  18 hours ago

                  none of the examples on this particular page feature the multiplication symbol ×

                  and why do you think that is?

                  “When a product involves a variable, it is customary to omit the symbol X of multiplication. Thus, 3 X n is written 3n and means three times n, and a X b is written ab and means a times b.”

                  Illiterate fraud.

              • mindbleach@sh.itjust.works
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                2 days ago

                your own textbook makes it clear that “doing brackets” means do what is inside the brackets first. Not what is outside the brackets.

                Which this troll admits when sneering “They say you can [simplify first] when there is Addition or Subtraction inside the Brackets.”

                Except when they sneer you must not do that, because there’s addition inside the brackets. 2(3*a+2*a)2 becomes 2(5*a)2, which gets a different answer, somehow. Or maybe it’s 2(3a+2a)2 becoming 2(5a)2 that’s different. One or the other is the SpEcIaL eXcEpTiOn to a rule they made up.

                Weird how nobody else in the world has this problem. Almost like a convention that requires special cases is fucking stupid, and if people meant (2(n))2, they’d just write that.

                Distributing 2 over a+b is not “doing brackets”; it is multiplication and comes afterwards.

                Which this troll literally underlines when sneering about textbooks they don’t read: “A number next to anything in brackets means the contents of the brackets should be multiplied.”

                Except when they insist distribution is totally different from multiplication… somehow. But if a product is one term and multiplying two things is a product and two things being multiplied is two terms, sure, fuck it, words don’t mean things.

                • FishFace@piefed.social
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                  1 day ago

                  I actually forgot the most obvious way in which Order of Operations is a set of conventions… Some countries say “BODMAS” (division then multiplication) whilst others say “PEMDAS” (multiplication then division)…

                  • mindbleach@sh.itjust.works
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                    1 day ago

                    They’re grouped, being essentially the same operation, but inverted. Ditto for addition and subtraction. There’s not a convenient word that covers both directions, like how exponents / order are the same for positive and negative powers.

                    Convention is saying 1/ab is 1/(ab) instead of (1/a)b, while 1/a*b is indeed (1/a)b. The latter of which this troll would say is a syntax error, because juxtaposition after brackets is foreboden… despite modern textbook examples.