this post was submitted on 12 Dec 2023
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You lost me on the section when you started going into different calculators, but I read the rest of the post. Well written even if I ultimately disagree!
The reason imo there is ambiguity with these math problems is bad/outdated teaching. The way I was taught pemdas, you always do the left-most operations first, while otherwise still following the ordering.
Doing this for 6÷2(1+2), there is no ambiguity that the answer is 9. You do your parentheses first as always, 6÷2(3), and then since division and multiplication are equal in ordering weight, you do the division first because it's the left most operation, leaving us 3(3), which is of course 9.
If someone wrote this equation with the intention that the answer is 1, they wrote the equation wrong, simple as that.
The calculator section is actually pretty important, because it shows how there is no consensus. Sharp is especially interesting with respect to your comment because all scientific Sharp calculators say it's 1. For all the other brands for hardware calculators there are roughly 50:50 with saying 1 and 9.
So I'm not sure if you are suggesting that thousands of experts and hundreds of engineers at Casio, Texas Instruments, HP and Sharp got it wrong and you got it right?
There really is no agreed upon standard even amongst experts.
Hi, expert here, calculators have nothing to do with it. There's an agreed upon "Order of Operations" that we teach to kids, and there's a mutual agreement that it's only approximately correct. Calculators have to pick an explicit parsing algorithm, humans don't have to and so they don't. I don't look to a dictionary to tell me what I mean when I speak to another human.
Thanks for putting my thoughts into words, that's exactly why I hate math. It was supposed to be the logical one, but since it only needs to be parsed by humans it failed at even that. It's just conventions upon conventions to the point where it's notably different from one teacher/professor to the next.
I guess you can tell why I went into comp-sci (and also why I'm struggling there too)
No there isn't. I've never seen a single Year 7-8 Maths textbook that is in the slightest bit ambiguous about it. The Distributive Law has to literally always be applied (hence why it's a law). dotnet.social/@SmartmanApps/110819283738912144
The order of operations is not the same as the distributive law.
The first step in order of operations is solve brackets. The first step in solving unexpanded brackets is to expand them. i.e. The Distributive Law. i.e. the ONLY time The Distributive Law ISN'T part of order of operations is when there's no unexpanded brackets in the expression.
The distributive law has nothing to do with brackets.
The distributive law can be written in PEMDAS as a(b+c) = ab + ac, or PEASMD as ab+c = (ab)+(ac). It has no relation to the notation in which it is expressed, and brackets are purely notational.
BWAHAHAHA! Ok then, what EXACTLY does it relate to, if not brackets? Note that I'm talking about The Distributive LAW - which is about expanding brackets - not the Distributive PROPERTY.
a(b+c)=(ab+ac) actually - that's one of the common mistakes that people are making. You can't remove brackets unless there's only 1 term left inside, and ab+ac is 2 terms.
No, never. ab+c is 2 terms with no further simplification possible. From there all that's left is addition (once you know what ab and c are equal to).
Yep, they're a grouping symbol. Terms are separated by operators and joined by grouping symbols.
You are off your meds
Noted that you were unable to tell me what The Distributive Law relates to (given your claim it's not brackets).
You are unhinged