I mean, arithmetic order is just convention, not a mathematical truth. But that convention works in the way we know, yes, because that’s what’s… well… convention
Comment on I dunno
marcos@lemmy.world 1 month agoSome people insist there’s no “correct” order for the basic arithmetic operations. And worse, some people insist the correct order is parenthesis first, then left to right.
Both of those sets of people are wrong.
SkyeStarfall@lemmy.blahaj.zone 1 month ago
SmartmanApps@programming.dev 3 weeks ago
I mean, arithmetic order is just convention
Nope, rules arising from the definition of the operators in the first place.
not a mathematical truth
It most certainly is a mathematical truth!
But that convention works in the way we know, yes, because that’s what’s… well… convention
The mnemonics are conventions, the rules are rules
SkyeStarfall@lemmy.blahaj.zone 3 weeks ago
The rules are socially agreed upon. They are not a mathematical truth. There is nothing about the order of multiple different operators in the definition of the operators themselves. An operator is simply just a function or mapping, and you can order those however you like. All that matters is just what calculation it is that you’re after
SmartmanApps@programming.dev 3 weeks ago
The rules are socially agreed upon
Nope! Universal laws.
They are not a mathematical truth.
Yes they are! 😂
There is nothing about the order of multiple different operators in the definition of the operators themselves
That’s exactly where it is. 2x3 is defined as 2+2+2, therefore if you don’t do Multiplication before Addition you get wrong answers
you can order those however you like.
No you can’t! 😂 2+3x4=5x4=20, Oops! WRONG ANSWER 😂
All that matters is just what calculation it is that you’re after
And if you want the right answer then you have to obey the order of operations rules
marcos@lemmy.world 1 month ago
Social conventions are real, well defined things. Some mathematicians like to pretend they aren’t, while using a truckload of them; that’s a hypocritical opinion.
That’s not to say you can’t change them. But all of basic arithmetic is a social convention, you can redefine the numbers and operations any time you want too.
SmartmanApps@programming.dev 3 weeks ago
Social conventions are real, well defined things
So are the laws of nature, that Maths arises from
Some mathematicians like to pretend they aren’t, while using a truckload of them; that’s a hypocritical opinion
No, you making false accusations against Mathematicians is a strawman
That’s not to say you can’t change them
You can change the conventions, you cannot change the rules
But all of basic arithmetic is a social convention
Nope, law of nature. Even several animals know how to count.
you can redefine the numbers and operations any time you want too
And you end up back where you started, since you can’t change the laws of nature
SmartmanApps@programming.dev 3 weeks ago
Some people insist there’s no “correct” order for the basic arithmetic operations.
And those people are wrong
And worse, some people insist the correct order is parenthesis first, then left to right
As per Maths textbooks
Both of those sets of people are wrong
All Maths textbooks are wrong?? 😂
Petter1@discuss.tchncs.de 5 weeks ago
Well, this is just a writing standard that is globally agreed on,
The writing rules are defined by humans not by natural force
(That one thing and another thing are two things, is a rule from nature, as comparison)mindbleach@sh.itjust.works 3 weeks ago
Save yourself the trouble - Smartman Apps is a crank. They categorically will not comprehend the difference between the notation we made up and how numbers work. Dingus keeps saying ‘animals can count’ like that proves parentheses-first is completely different! from distribution.
Why’d Russel and Whitehead bother with the Principia Mathematica when they could just point to Clever Hans?
SmartmanApps@programming.dev 3 weeks ago
this is just a writing standard that is globally agreed on
No, it’s a universal rule of Maths
The writing rules are defined by humans not by natural force
Maths is for describing natural forces, and is subject to those laws
That one thing and another thing are two things, is a rule from nature
Yep, there are even some animals who understand that, and all of Maths is based upon it.
MotoAsh@piefed.social 1 month ago
Hopefully you can see where their confusion might come from, though. PEMDAS is more P-E-MD-AS. If you have a bunch of unparenthesized addition and subtraction, left to right is correct. A lot of like, firstgrader math problems are just basic problems that are usually left to right (but should have some extras to highlight PEMDAS somewhere I’d hope).
So they’re mostly telling you they only remember as much math as a small child that flunked.
SpaceCadet@feddit.nl 1 month ago
If you have a bunch of unparenthesized addition and subtraction, left to right doesn’t matter.
1 + 2 - 3 = 1 - 3 + 2 = -3 + 2 + 1
MotoAsh@piefed.social 1 month ago
True, but as with many things, something has to be the rule for processing it. For many teachers as I’ve heard, order of appearance is ‘the rule’ when commutative properties apply. … at least until algebra demands simplification, but that’s a different topic.
SpaceCadet@feddit.nl 1 month ago
Well the rule is: any order goes. Summation is commutative.
SmartmanApps@programming.dev 3 weeks ago
That’s because students often make mistakes with signs when they do it in a different order, so we tell them to stick to left to right
kuberoot@discuss.tchncs.de 5 weeks ago
Right, because 1-2-3=3-2-1.
SmartmanApps@programming.dev 3 weeks ago
No, 1-2-3=-3-2+1. You changed the signs on the 1 and the 3.
howrar@lemmy.ca 5 weeks ago
You flipped the sign on the 3 and 1.
Feathercrown@lemmy.world 1 month ago
PE(MD)(AS)
Now just remember to account for those parentheses first…
SmartmanApps@programming.dev 3 weeks ago
Those Brackets don’t matter. I don’t know why people insist it does
Feathercrown@lemmy.world 3 weeks ago
They do, it’s grouping those operations to say that they have the same precedence. Without them it implies you always do addition before subtraction, for example.
SmartmanApps@programming.dev 3 weeks ago
You can do addition and subtraction in any order and it’s still correct
orbitz@lemmy.ca 1 month ago
Huh I just remembered the orders of arithmetic but parentheses trump all so do them first (I use them in even the calculator app). Mean I assume that’s that that says but never learned that acronym is all. Now figuring out categories of words;really does my noodle in sometimes. Cause some words can be either depending on context. Math when it’s written out has (mostly) the same answer. I say mostly because somewhere in the back of my brain there are some scenarios where something more complicated than straight arithmetic can come out oddly but written as such should come out the same.