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submitted 1 year ago by Toes@ani.social to c/196@lemmy.blahaj.zone

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[-] SmartmanApps@programming.dev 1 points 8 months ago

It’s only a wrong answer

Really? You want to do that again? Ok, fine... If I have 1 2 litre bottle of milk, and 4 3 litre bottles of milk - i.e. 2+3x4 - how many litres of milk do I have?

you would with the standard order of operations

The definition of 5 as being 1+1+1+1+1 has nothing to do with order of operations.

there is no law of the universe that makes 5 look like that

No, but there is a rule of Maths which defines it.

switch the definitions of the symbols 5 and 4 if we did it all at once and revised old math expressions to match the new standard

In other words everything would be the same as now but we just switched the notation around. I already said that to you a while back. Now you're getting it.

there is no reason the order of operations is what it is other than that is how someone decided to write it

Got nothing to do with how it's written - Maths is written differently in many different countries, and yet the underlying order of operations rules are universal.

I’m not saying you can take any expression and get the same answer by doing addition before multiplication

And if it's not the same answer then it's wrong. You're nearly had it.

I’m saying you can take any problem and get the correct answer by doing addition before multiplication

And I told you you can't. Waiting on a proof from you. Start with 2+3x4 - show me how you can get the correct answer by doing addition first - it's a nice simple one. :-)

that means I would use the expression 2+(3x4) because 2+3x4

They're literally the same thing.

All I am saying is that you can still use numbers to solve problems with an altered order of operations, or by altering any part of the system of notation

And I told you that it's impossible. Changing the notation doesn't change the Maths.

As you can see, I used my altered math notation to find the correct answer

BWAHAHAHAHA! Nope! I see you putting brackets around the multiplication to make sure it gets done first - same as if you hadn't used brackets at all! It's the exact same notation we use now, just with some redundant brackets added to it! And, predictably, you left the addition for last.

Ok, let's take your example and do addition first (like you claimed can be done)...

15²+50²=15x15+50x50=15x65x50=48,750. But 15²+50² is 2,725 according to my calculator. Ooooh, different answers - I wonder which one is right... I wonder which one is right...???

Thanks for proving it can only be done by following the order of operations rules (just like I've been saying to you all along). Bye now.

[-] AdrianTheFrog@lemmy.world 1 points 8 months ago

I"m beginning to wonder if you are willfully misunderstanding my point. Or perhaps you have sunk so much time into this argument you assume I must be wrong. Take another look at my third and fifth paragraphs. I promise, I am not trying to say what you think I'm trying to say.

I see you putting brackets around the multiplication to make sure it gets done first - same as if you hadn’t used brackets at all! It’s the exact same notation we use now, just with some redundant brackets added to it! And, predictably, you left the addition for last.

All I did was use the expression necessary to evaluate correctly with the altered order of operations. There are, in fact, times when you can remove brackets that you would otherwise need, for example (x+4)(x-2) would no longer need brackets. The fact that "old" expressions often have to be written with new brackets to evaluate correctly with an altered order of operations is something I fully understand. The presence of brackets where there would be none otherwise does not invalidate my point.

15²+50²=15x15+50x50=15x65x50=48,750. But 15²+50² is 2,725 according to my calculator. Ooooh, different answers - I wonder which one is right… I wonder which one is right…???

What? I never wrote 15²+50². That is an expression you copied incorrectly. Your incorrectly copied expression has little relevance to the problem at hand.

Ok, fine… If I have 1 2 litre bottle of milk, and 4 3 litre bottles of milk - i.e. 2+3x4 - how many litres of milk do I have?

If we were doing math with an altered order of operations, the expression 2+3x4 is just simply wrong. 2+(3x4) is the expression you need. If you try to do math the same as it is with the regular order of operations, it will not work. But that does not mean math with an altered order of operations is useless. It is still math. It can still be used to "study of the measurement, properties, and relationships of quantities and sets using numbers and symbols".

I fully understand that to correctly evaluate an expression written with a certain order of operations in mind, you need to use that order of operations. If someone wrote an expression with a different order of operations in mind, you could solve it with a different order of operations and still get what the author of the expression intended. For example, I write the equation a+2xa-2 with my order of operations, expecting you to use the same order of operations, and tell you to simplify. If you get 3a-2, that is wrong, because you used an order of operations different than the one I intended to be used to solve the problem. Imagine, for a moment, an alternate universe where everyone uses a different order of operations and a+2xa-2 simplifies to a^2-4. All I am trying to say is that that their math, with a different order of operations, would be no less useful then our math.

In summary, my only claim is that you can still use a different order of operations to manipulate numbers and solve real world problems.

Waiting on a proof from you.

I wrote and evaluated all of those expressions in my last comment with a different order of operations in mind, and was still able to come to the correct answer.

[-] SmartmanApps@programming.dev 1 points 8 months ago* (last edited 8 months ago)

I wasn't going to reply any more, but I see now you don't understand terms either, so one more time for old time's sake (and maybe you might finally get it)...

perhaps you have sunk so much time

You know teachers don't get paid for helping students outside class time right?

assume I must be wrong

No assumption needed. What you are proposing is literally impossible. I've been saying that all along.

Take another look at my third and fifth paragraphs.

Ok...

I’m not saying you can take any expression and get the same answer by doing addition before multiplication

And so far you haven't been able to show it works for any expression at all! Not even one expression! Just like I said would happen.

All I am saying is that you can still use numbers to solve problems with an altered order of operations

And I said you can't, and you haven't! All you did was put brackets around the multiplication to make sure we were still following the only order of operations that works! You have still not shown an actual instance where one can actually do addition first and get a right answer, not one! The idea that one could use addition first as an "alternate order of operations" is thus pure fantasy, just like I've been saying all along. It's literally impossible.

for example (x+4)(x-2) would no longer need brackets

Yes it would! (x+4) is one term - that's what the brackets means - "these things are all together". If you remove that, because "addition first", it's now two terms, so the whole expression is two terms (instead of one), x, and 4(x-2) (which is a mistake people make when they write 8/2(2+2) as 8/2x(2+2) - just turned 2 terms into 3 terms and changed the answer!). Every example you've done so far you've used brackets to escape from having to do addition first, and the very same thing would therefore apply here - no brackets, no escaping "addition first" approach, brackets before addition leads to x+4(x-2)=x+(4x-8) =5x-8, which is not the product of (x+4) and (x-2).

The presence of brackets where there would be none otherwise does not invalidate my point

No, the fact that you've not been able to show a single instance of where addition before multiplication would work does. You can't show "a way to solve this in an addition first world" when it's literally impossible for an "addition first world" to exist in the first place.

I never wrote 15²+50²

...and I removed the brackets to show that addition first doesn't work (since you keep putting in brackets to revert "addition first" back to the only order of operations that actually works).

It can still be used to “study of the measurement, properties, and relationships of quantities and sets using numbers and symbols”

And you've still not shown how. Every example you've used so far you've put in brackets to your (supposed) "addition first" so that we were evaluating it using the only order of operations that works. In other words, no, you can't use "addition first" to “study of the measurement, properties, and relationships of quantities and sets using numbers and symbols” - you used the regular order of operations to do it! You haven't shown a single example of where addition first could be used to do it.

you need to use that order of operations

You need to use an order of operations that gives a correct answer, of which there is only one - a fact you keep trying to avoid.

different order of operations and a+2xa-2 simplifies to a^2-4

No it wouldn't, cos now you're ignoring terms as well. As per my earlier working out, it would simplify to 5x-8 unless you also changed the definition of terms. Do you see yet why it's impossible to have an "alternate order of operations"?

All I am trying to say is that that their math, with a different order of operations, would be no less useful then our math

And you've completely failed to show a single instance where this is true - which is what I've been saying all along, it's impossible to have another set of order of operations that works. You keep pre-supposing it's possible, but then add brackets to the multiplications so that we follow the actual correct order of operations, the only order of operations that works.

my only claim is that you can still use a different order of operations to manipulate numbers and solve real world problems

And you've still failed to solve a single problem using addition first, because it's still a fact it's literally impossible to do so.

was still able to come to the correct answer

by using the only order of operations that works. i.e. multiplication before addition.

Now I really am done - I'm not going any further down this rabbit hole of whatever other Maths you may not understand either (this post it was Terms - who knows what's next)...