Poll: Solve a simple math problem

[madwarper]

not on short answers, but 8+4-2+3 will give a diffrent answer to 8+4+3-2 because you work out the addition, 8+4 and 2+3 and subtract them, thats how it works,

Wrong.
8+4=12-2=10+3=13
8+4=12+3=15-2=13

13=13.

you block groups of numbers together that have not been broken up by a diffrent mathematical symbol. thats why typing 8+4-2+3 into a simple calculator will give a diffrent answer to a proper scientific one.

You are completely wrong.

 

[Lukeje]

Only if you define it as such. The field could be equally well defined with
infinity - infinity = infinity.

A number minus itself not being 0 is inconsistent with basic arithmetic. You could just as easily define 3 - 3 = 3, but it simply doesn?t make sense within the system of math that we use.

?infinity ? infinity = infinity? only works if you accept that you?re not going to treat infinity as a number.

My point is that you've made an assumption and not stated it. What is the converse of infinity + n = infinity (*)? One can of course make the assumption that infinity - infinity = 0. This leads to contradictory results and thus seems like a bad candidate, as you've discovered. One can make the better assumption that infinity - infinity = infinity and then the contradiction goes away; subtracting infinity from both sides of (*) results in the original equation.

 

[the.gill123]

oh i remember its called SIMPIFICATION OF NUMBERS!

 

[BloodSquirrel]

not on short answers, but 8+4-2+3 will give a diffrent answer to 8+4+3-2 because you work out the addition, 8+4 and 2+3 and subtract them, thats how it works, you block groups of numbers together that have not been broken up by a diffrent mathematical symbol. thats why typing 8+4-2+3 into a simple calculator will give a diffrent answer to a proper scientific one.

Simple calculators do not give you the correct answer. They're designed to be used *after* a human has determined the correct order of operations. A calculator that allows you to enter the entire equation before calculating it will give the same answer to 8+4+3-2 as 8+4-2+3.

Try it for yourself:

http://web2.0calc.com/

 

[FrossetMareritt]

not on short answers, but 8+4-2+3 will give a diffrent answer to 8+4+3-2 because you work out the addition, 8+4 and 2+3 and subtract them, thats how it works, you block groups of numbers together that have not been broken up by a diffrent mathematical symbol. thats why typing 8+4-2+3 into a simple calculator will give a diffrent answer to a proper scientific one.

No... it won't. You must have hit a different operator because I keep getting 13 no matter what order I put them in as long as the 8,4 and 3 are positive and 2 is negative.

 

[Syphous]

Now I must be reading this wrong. None of this thread makes sense to me.

1+1+1+1+1+1+1+1+1+1-1+1+1+1+1+1+1*0=?

I'm seeing all these ones that don't matter because in the end it's multiplied by 0. Multiply anything by 0 and the answer is 0.

 

[the.gill123]

alright fine i will conceed i'm being shouted down on all fronts so i must be wrong

 

[madwarper]

Now I must be reading this wrong. None of this thread makes sense to me.

1+1+1+1+1+1+1+1+1+1-1+1+1+1+1+1+1*0=?

I'm seeing all these ones that don't matter because in the end it's multiplied by 0. Multiply anything by 0 and the answer is 0.

Deja Vu all over again.

Yes, there is something being multiplied by 0. But, what is "it", that's being multiplied?

If you're thinking that it's the sum of the previous numbers, you're mistaken.

In order of operations, multiplication happens before addition/subtraction. The sole 1 at the end become 0. And, then you take the sum of the rest of the numbers as normal.

 

[BloodSquirrel]

One can of course make the assumption that infinity - infinity = 0. This leads to contradictory results and thus seems like a bad candidate, as you've discovered.

That is an actual way to construct a mathimatical proof, which was the entire point in the first place. If you treat infinity like a number and attempt to perform normal aritmetic operations on it (such as infinity - infinity = 0), you get invalid results. Ergo, infinity can not be treated that way.

I'm not saying that infnity - infinity = 0 is valid. I'm saying that it would be valid if infinity were a number, which, as demonstrated, doesn't work.

 

[Secret world leader (shhh)]

Shit! i fucked up and voted 15 instead of 14! I'm not stupid, I swayer!

 

[Syphous]

Now I must be reading this wrong. None of this thread makes sense to me.

1+1+1+1+1+1+1+1+1+1-1+1+1+1+1+1+1*0=?

I'm seeing all these ones that don't matter because in the end it's multiplied by 0. Multiply anything by 0 and the answer is 0.

Deja Vu all over again.

Yes, there is something being multiplied by 0. But, what is "it", that's being multiplied?

If you're thinking that it's the sum of the previous numbers, you're mistaken.

In order of operations, multiplication happens before addition/subtraction. The sole 1 at the end become 0. And, then you take the sum of the rest of the numbers as normal.

Right, gotcha. 14. Okay.

 

[Lukeje]

One can of course make the assumption that infinity - infinity = 0. This leads to contradictory results and thus seems like a bad candidate, as you've discovered.

That is an actual way to construct a mathimatical proof, which was the entire point in the first place. If you treat infinity like a number and attempt to perform normal aritmetic operations on it (such as infinity - infinity = 0), you get invalid results. Ergo, infinity can not be treated that way.

I'm not saying that infnity - infinity = 0 is valid. I'm saying that it would be valid if infinity were a number, which, as demonstrated, doesn't work.

No. You seem to have this strange idea of `number'. If it were being treated as a `number', then infinity + n =/= infinity. This is a property of general numbers. If you have to specify a special rule for addition of infinity, then why should it behave `normally' under subtraction from itself? You have only proved that a system with subtraction of two infinities defined to be zero is inconsistent. This is not the same as saying that all sets of numbers including infinity are inconsistent.

 

[Jonluw]

I answered 16 because I didn't notice the minus sign.
Just assumed they were all pluses *facepalm*

 

[Kragg]

alright fine i will conceed i'm being shouted down on all fronts so i must be wrong

in the end they want you to understand why you are wrong, not trying to beat you in a contest of minds or anything

 

[karamazovnew]

This is so funny... 13 pages and going. As a person currently trying to make sense of the paradoxes of near light-speed travel, seeing people screw up such a simple formula and still thinking they are right is just... wow.

 

[Norendithas]

This is so funny... 13 pages and going. As a person currently trying to make sense of the paradoxes of near light-speed travel, seeing people screw up such a simple formula and still thinking they are right is just... wow.

I like seeing all these people get heated up so much over a little math problem. A simple one, at that.

 

[Jonluw]

0=1-1
0=1-1+1-1
0=1-1+1-1+1-1
0=1-1+1-1+1-1+.....
0=1+(-1+1)+(-1+1)+....
0=1+0+0+0+...
0=1

I don't know if anyone has replied to this yet, and I can't be bothered to read all 13 pages, so I'll just point out you've put on the parentheses the wrong way. My apologies in advance if I'm repeating old news here.
When you do what you did, you'll end up with this:

0=1-1
0=1-1+1-1
0=1-1+1-1+1-1
0=1-1+1-1+1-1+.....
0=1+(-1+1)+(-1+1)+....(-1+1)-1
0=1+0+0+0+...-1
0=1-1

0 only equals "1-1+1-1..." so long as the line of ones ends in "-1"
However, for all of the parentheses in the line to each equal 0, the way you've set it up, the line of ones has to end in "+1"

Edit: Yup, seems like it's already been commented on. Sorry.

 

[Thanatos5150]

Tricked by PEMDAS.

That'll teach me tot take shortcuts.

 

[p3t3r]

the biggest challenge is counting all those 1's it is 14 btw