💡𝚂𝗆𝖺𝗋𝗍𝗆𝖺𝗇 𝙰𝗉𝗉𝗌📱

  • 231 Posts
  • 210 Comments
Joined 2 years ago
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Cake day: November 25th, 2023

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  • So if I see something like “5-(2+4)” I will just remove the subtraction operator and call it a day

    Nope. Never said anything of the sort.

    Smartman on the internet said so

    No I didn’t, but nice try at a strawman 😂

    not everyone on the internet is a native english speaker. Everyone but you knew what was meant.

    There is no such thing as “implied multiplication” in any language. They are called Terms/Products in whatever language that book is using.



  • Do you think you’re above them?

    You know we’re talking about Year 7 Maths, right? 😂

    Elementary school teaches you the fundamentals to your future education

    but NOT The Distributive Law, which is taught in high school, in Algebra

    I didn’t say you were wrong about math

    You said “I don’t think you’re right”, and followed it up with “Ill informed”, to a Maths teacher.

    I said you were wrong about English that is used in relation to math

    And you were wrong about that too

    Clearly this isn’t a strong suit of yours

    What you mean is you clearly can’t rebut any of it

    However, stop acting like you know everything

    I know everything about high school Maths - I teach it

    you clearly don’t

    There you go again calling a Maths teacher wrong about Maths 😂

    You’re using some very strange logic to argue you’re right

    You think Maths textbooks use very strange logic??

    it doesn’t make any sense

    read this then. Contains Maths textbooks


  • Please read this section of Wikipedia which talks about these topics better than I could

    Please read Maths textbooks which explain it better than Joe Blow Your next Door neighbour on Wikipedia. there’s plenty in here

    It shows that there is ambiguity in the order of operations

    and is wrong about that, as proven by Maths textbooks

    especially niche cases there is not a universally accepted order of operations when dealing with mixed division and multiplication

    That’s because Multiplication and Division can be done in any order

    It addresses everything you’ve mentioned

    wrongly, as per Maths textbooks

    Multiplication denoted by juxtaposition (also known as implied multiplication)

    Nope. Terms/Products is what they are called. “implied multiplication” is a “rule” made up by people who have forgotten the actual rules.

    s often given higher precedence than most other operations

    Always is, because brackets first. ab=(axb) by definition

    1 / 2n is interpreted to mean 1 / (2 · n)

    As per the definition that ab=(axb), 1/2n=1/(2xn).

    [2][10][14][15]

    Did you look at the references, and note that there are no Maths textbooks listed?

    the manuscript submission instructions for the Physical Review journals

    Which isn’t a Maths textbook

    the convention observed in physics textbooks

    Also not Maths textbooks

    mathematics textbooks such as Concrete Mathematics by Graham, Knuth, and Patashnik

    Actually that is a Computer Science textbook, written for programmers. Knuth is a very famous programmer

    More complicated cases are more ambiguous

    None of them are ambiguous.

    the notation 1 / 2π(a + b) could plausibly mean either 1 / [2π · (a + b)]

    It does as per the rules of Maths, but more precisely it actually means 1 / (2πa + 2πb)

    or [1 / (2π)] · (a + b).[18]

    No, it can’t mean that unless it was written (1 / 2π)(a + b), which it wasn’t

    Sometimes interpretation depends on context

    Nope, never

    more explicit expressions (a / b) / c or a / (b / c) are unambiguous

    a/b/c is already unambiguous - left to right. 🙄

    Image of two calculators getting different answers

    With the exception of Texas Instruments, all the other calculator manufacturers have gone back to doing it correctly, and Sharp have always done it correctly.

    6÷2(1+2) is interpreted as 6÷(2×(1+2))

    6÷(2x1+2x2) actually, as per The Distributive Law, a(b+c)=(ab+ac)

    (6÷2)×(1+2) by a TI-83 Plus calculator (lower)

    Yep, Texas Instruments is the only one still doing it wrong

    This ambiguity

    doesn’t exist, as per Maths textbooks

    “8 ÷ 2(2 + 2)”, for which there are two conflicting interpretations:

    No there isn’t - you MUST obey The Distributive Law, a(b+c)=(ab+ac)

    Mathematics education researcher Hung-Hsi Wu points out that “one never gets a computation of this type in real life”

    And he was wrong about that. 🙄

    calls such contrived examples

    Which notably can be found in Maths textbooks





  • You are the brickest wall on lemmy

    Says person who hasn’t looked this up in a Maths textbook 😂

    Either out of undiagnosed neurodivergence or some aggravating character gimmick

    Neither, I’m a Maths teacher

    you pretend there is one true way to do a thing

    There’s no pretending involved, it’s in Maths textbooks

    The commutative property means addition can happen in any order

    Yep, and??

    But multiplication and distribution are totally different

    Nope! They can also be done in any order

    you will never ever shut the fuck up about splitting that hair

    Got no idea who you think you’re talking to, but I never said Multiplication and Division are different

    It’s dogma

    No, it’s the rules of Maths as found in Maths textbooks 😂

    You’ve internalized one set of rigid instructions

    ALL Mathematicians have, if you’re going to put it like that.

    declared them the rules of all mathematics

    As found in Maths textbooks

    to the point you insist Reverse Polish Notation has parentheses

    It adds them in the background, so that you don’t have to - if it didn’t it would return wrong answers - you not having to type them in doesn’t mean they aren’t getting added

    It literally cannot

    …give correct answers without putting each paired operation into brackets

    Yet it’s an equally valid way to write and do math

    and obeys the EXACT SAME RULES 🙄

    It gets the same results

    because it obeys the same rules 🙄

    despite distribution being impossible

    Not impossible at all. Someone even wrote it in one of the other comments! 😂

    Last time I tried wedging this uneniable fact through any gap in your mortar

    you found there were no gaps 😂

    you smugly declared you’d found a way

    And as these very comments show, I’m not the only one to have done so! 😂

    then explained multiplication, not distribution

    No, Distribution.

    Zero self-awareness

    Well, you have zero awareness of what’s in Maths textbooks anyway 😂

    To this day, you are trying to be smug about a time you proudly contradicted yourself

    I have never contradicted myself. You calling Distribution “Multiplication” doesn’t make it Multiplication.

    I feel sorry for students who can’t just tell you

    My students do very well in their exams. How about you? 😂

    Go away, patience vampire

    Still can’t admit you were wrong then 🙄




  • I don’t think you’re right

    You don’t think Maths textbooks are right??

    The wiki page

    is full of disinformation. Note that they literally never cite any Maths textbooks

    as an example of “elementary arithmetic.”

    And whichever Joe Blow My Next Door Neighbour wrote that is wrong

    as an example in “elementary algebra.”

    Algebra isn’t taught until high school

    That implies that yes, this is arithmetic,

    No, anything with a(b+c) is Algebra, taught in Year 7

    the introduction of variables is what makes it algebra

    and the rules of Algebra, which includes a(b+c)=(ab+ac). There is no such rule in Arithmetic.

    It doesn’t matter what course finally teaches it to you

    It does if you’re going to argue over whether it’s Arithmetic or Algebra.

    not by definition part of that domain

    The Distributive Law is 100% part of Algebra. It’s one of the very first things taught (right after pronumerals and substitution).

    It’s been ages since I took it

    I teach it. We teach it to Year 7, at the start of Algebra







  • 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.

    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