Yet Another Stupid/funny Math Idea

[Ragnell]

Since you can determine if fractions are equivalent by cross multiplying, would 0/0 equal everything according to the zero-product property?

ex of cross-multiplying: 1/2=4/8

(1*8)=(4*2)

8=8

now: 0/0=100,000/37,259

(0*37,259)=(0*100,000)

0=0

equivalent

Now to prove it, I just need to insert variables.

0/0=Y/X

(0*X)=(0*Y)

So 0/0 really is undefined... Now I'm just waiting for some crazy math whiz to prove me totally and completely wrong... still waiting...

[Deity]

These sort of topics scare me. I hated math..I still do.

[GKSB]

Usually, when you put an = sign, it means, you know, they equal each other. 1/2 is the same as 4/8. 0/0 is not the same as 100,000/37,259. But, if you like just throwing random numbers together, then 2 + 5 = 6 and infinity = 1/3.

[Ragnell]

But when I cross multiply, they do come out equivalent. Assuming that there is some law which states that if you cross multiply the fractions are equal (sure hope there is, my teachers taught me that).

Edited March 11, 2009 by Ragnell

[GKSB]

It's the math you should have learned as a 3rd grader, dumb fuck. Anything you do with an equal sign only applies if they EQUAL each other. The value of 0/0 is undefined. The value of 100,000/37,259 is some constant. They don't equal. You can't shove an equal sign between them and expect that to somehow make it all better. It's like running a red light and complaining about getting hit; you have to follow ALL the rules of the system.

Maybe you're trying desperately to remember that cross-multiplication is used to solve variables. If you had written that 0/0 = 100,000 X /37,259, you'd use cross multiplication to solve for x. X would obviously equal zero.

Oh, and the concept of even and odd is rarely relevant in math, get that out of your head.

Edited March 11, 2009 by Crepe Knight

[California Mountain Snake]

H...

HU..

HURRRRRRRRRR!!!!!!!!!!!!!!!!!!!!!!!!1

[Nightmare]

H...

HU..

HURRRRRRRRRR!!!!!!!!!!!!!!!!!!!!!!!!1

And they said you'd never say that. Fucking liars.

[Ragnell]

I meant equal not even, sorry. And I still demonstrated how what I said works. It is undefined. Saying they aren't equal when I just explained how they are doesn't make sense.

But if you're going to be that way, look at my equation with variables inserted. When cross multiplied, they are equal, regardless of value. Which in every possible other case would mean they are totally equal.

And anyways, you can't divide by zero (from what I've been told) because you'll have X/0=Y/Z. Therefore, cross-multiplied, they are XZ=0Y. And unless X or Z are zero, the left side can't equal the right (which always equals zero). But in 0/0, X IS 0!

[GKSB]

Its not true. Saying that 0/0 = 100/532 is the same as saying that 2 + 2 = 5. The equal sign denotes that the two parts have the same value. It isn't a method used to prove whether or not they are equal. The variable has to be there if the statement is to be true. And I was technically wrong, X in the equation I gave would have to be 0/0, but it's a pointless equation either way.

You can't divide by zero because zero multiplied by anything is zero. Dividing it into something implies that something times zero will equal a constant. That can never be true, because anything and everything multiplied by zero is zero. Thus, it is undefined.

Edited March 11, 2009 by Crepe Knight

[Ragnell]

Understood, but cross multiplying proves that. Meanwhile 2+2=5 would come out 2+2/1=5/1 then 4=5. Not equivalent (you could just add them to make it simpler, but I'm showing cross-multiplication). Reread my reasoning on why dividing by zero doesn't work and you'll see we're saying the same thing except I'm using numbers and you're using words. Now I understand that 0/0 equaling everything is stupid and has no practical uses, but it is a fault in our math that actually works. Sorta like a glitch of sorts.

What I'm trying to say is that if two numbers cross-multiply to the same thing, they ARE equal. So if 0/0 cross multiplies with anything it will come out to 0=0 (which is equal).

[Metal Rabbit]

The inverse of 1 is 1.

[GKSB]

You prove my point, you can't mash two terms together and expect them to be equal. You're using the property of zeros as justification, but like you yourself are saying, what you are doing requires that you divide by zero. That gives you an undefined answer. Plus, if you're using the system incorrectly, you can't expect it to make sense. You are using the system incorrectly and then coming to conclusions because of it. Cross-multiplication is only even used when a variable is present, for one thing; and it only applies if the terms across the equal sign are equal. You know before hand that 0/0 does not equal anything. So you create an untrue argument, and then make conclusions from that.

And you really are breaking the rules. Think of the algebraic definition of division; a/b = c if and only if c x b = a. it doesn't work if b = 0, because c x 0 will always be 0, and you cannot get a again.

0/0 is undefined via limits. If you have two functions that approach zero at exactly the same rate divided by each other, they cancel out and approach 1 (such as if F(x) = x and G(x) = x, they both approach 0, but divided, instead of getting 0 /0 , you get 1). 0/0 doesn't exist, it requires other factors to lead to it that cannot happen in math.

[Ragnell]

While I mostly agree with you (again) I feel the need to point out that dividing by 0 makes some sense here. In this problem, both a and b are 0. a/b=c c*b=a -> c*0=0 So it will be 0=0 for any value of c. Again, 0/0 can equal anything (but does equal undefined by definition).

And while cross-multiplication is most often used for when variables are present, that is not at all the only time it may be used. I'm simply pointing out a funny fact that results from the zero product property. It has no practical explanation.

By the way, I noticed this whole thing when trying to figure if 0/0 was undefined because it had zero in the denominator, 0 because it had 0 in the numerator, or 1 because it had the same number in both the numerator and denominator.

Edited March 11, 2009 by Ragnell

[lolDeath]

Being a member on the same site as Crepe is educational, I can't get over how funny this is to me.

He is the only person I know who will actually take the time to educate someone while saying "lolno".

I'd say he was smart, if he wasn't a Texan pianist (I am going to make this into slang for something).

Edited March 11, 2009 by Death

[GKSB]

While I mostly agree with you (again) I feel the need to point out that dividing by 0 makes some sense here. In this problem, both a and b are 0. a/b=c c*b=a -> c*0=0 So it will be 0=0 for any value of c. Again, 0/0 can equal anything (but does equal undefined by definition).

It doesn't, because you can't divide by zero in the first place by that definition. Get it through your head, numbnuts. You might as well multiply by Purple and make the whole equation Beige, because starting off with that equation is STILL breaking all of the rules. The division definition only applies if a/b equals c in the first place. Your 'equation' doesn't, its gibberish. You can't try and use a broken system then to justify itself, because you already know its using false parameters and that anything it comes up with doesn't mean anything.

And while cross-multiplication is most often used for when variables are present, that is not at all the only time it may be used. I'm simply pointing out a funny fact that results from the zero product property. It has no practical explanation.

It is always used in such a case, there's no point to use it otherwise.

By the way, I noticed this whole thing when trying to figure if 0/0 was undefined because it had zero in the denominator, 0 because it had 0 in the numerator, or 1 because it had the same number in both the numerator and denominator.

It's not. It's considered undefined because of how it has to be arrived at through calculus (or, more appropriately, how it can't be arrived at through calculus). If you haven't taken it, you don't realize that all these numbers and graphs have actual origins; stating things algebraically is like putting letters together because they spell words. Stating things using calculus is forming sentences out of those words. You can't arrive at 0/0 in any meaningful way, and it means nothing in of itself; so it is undefined.

Being a member on the same site as Crepe is educational, I can't get over how funny this is to me.

He is the only person I know who will actually take the time to educate someone while saying "lolno".

I'd say he was smart, if he wasn't a Texan pianist (I am going to make this into slang for something).

Nothing's as satisfactory as watching people wither before the truth. It'll be amazing slang.

[Kriemhild]

I don't get how so many people could NOT understand this. It's so simple. No number could ever be divided by zero. Zero is nothing. You can't divide something by nothing. You can't even divide nothing by nothing. 0 can never be the denominator. So this 0/0 isn't a number or a fraction or even real. It's just a figment of some people's imaginations.

[Bohemund]

0/0 is undefined. You cannot use it in math for anything. Nothing out of nothing doesn't equal whatever number you wish. Zero has special properties which make a problem lolgameover in math.

[Jyosua]

Actually it's called indeterminate. As a Calc 3 and Differential equations student, as well as a math tutor, I will kill the next person that says you can set 0/0=100,000/37,259. You can't do it. 0/0 has to ALREADY be equal to 100,000/37,259 in order for you to legally put an equal sign there and then cross multiply, regardless of if it ends up working. In mathematical proofs, you are not allowed to assume, which is what you just did. The moment you try to set something equal to something else, before you know whether it's true or not, in order to prove it, you just failed at making a legitimate proof. Any teacher will tell you this.

[Liz]

As a Calc 3 and Differential equations student, as well as a math tutor, I will kill the next person that says you can set 0/0=100,000/37,259

you can set 0/0=100,000/37,259

i iz ded nao?

XD

lolololololololololololololololololololololol!

ilu Jyosua!

:D

[Jyosua]

B&

[Liz]

B&

:D