I still think this is straying off topic a little, the formula used was the one given. And I can't see how, using that formula results in 5 equalling infinity.
Lefty holds a good point, but because you can add zeros for ever you'll never get any closer or further then 5, the number is undefined.

its a lot easier to look back at this now than to try to learn it this way when you first learn about division. just like taking the square root of a negative number, you were probably told that it can't be done. it can be done, its just easier to ignore it when you're first learning about square roots.

that website just says that the limit as x goes to zero is infinity. the function is undefined at that point, but the function still goes towards some value.

sol, do you agree that the limit of 1/x as x goes to infinity is zero?

i wouldn't give him that much credit, jp, we are talking about the person that said "This is stupid. I didn't bother looking at the calculus. All I saw was him trying to use L Hospital's rule, which makes him more of a moron."

"He would agree the the limit goes there, but that doesn't make x/0 = infinity. He's distinguishing between lim h-> 0 x/h and x/0. Which is okay, I suppose. Limits can certainly exist where the function doesn't"

Horray, you figured it out, that was all I was saying.

"i wouldn't give him that much credit, jp, we are talking about the person that said "This is stupid. I didn't bother looking at the calculus. All I saw was him trying to use L Hospital's rule, which makes him more of a moron."

Those were my first impressions. I didn't think he was just trying to take a limit in the proof, or else he wouldn't have made it more complicated. But still, this isn't an argument if we're just saying that lim as x---> 0 of 5/x, it is infinity. Because i'll agree with that. However, if you're gonna be silly and say that it allows for 5/0 to exist, then i'll dissagree. What do you think they show non continuity in a graph? And besides, what is so bad about saying that. It is moronic to try and use anything to prove that 5/0 actually equals 0. Almost as moronic as if someone tried to add of subtract infinity so that they could prove that .9999R = 1. Oh wait, people do that too.

Oh, so you're saying that everyone else dissagrees with me.

"There is no argument against .999... not equalling 1."

Yup, there isn't an argument against the fact that .99999 isn't 1. Thank you, you just said it yourself.

"It's already been proven many times over with various proofs, ranging from limits to algebra to logic."

Logic, eh? What would that be for you? Ooooooo it's really close so let's just make it 1 because that's easier to do. Algebra, that really worked too. 9.999R/10 = .99999R. 9.99999R - .99999R = 9. 9/9 = 1. I pointed out that's wrong because you can't add or subtract infinity like that. Limits? That just says what it's infinitely approaching, but you have to realize that technically it never gets there.

"x=1
1 / 3 = 0.333..."

More rounding, eh? 1 / 3 isn't 0.3333 exactly, there's just no other way to express it.

you want a problem too eh? .99999R * 10 = 9.99999R, 1 * 10 = 10.

Jp is in like AP calculus advanced level 10. I can't keep up with it. Aleph-1... amazing.

I'm actually out of school, Solbadguy500. And I did do the highest level of maths available, but it didn't involve aleph-1. I picked that concept up from elsewhere.

Even worse - There exists another infinity, aleph-2, that is actually larger then aleph-1 (Despite them both being infinities. It's provable).

However, multiplying the equation 0.0R1 = 0 by aleph-2 gives you aleph-2 = 0. Which implies that 0 > 0. Obviously wrong, then.

(Incidentally, Aleph-1 is the number of integers, and Aleph-2 is the number of real numbers)

"are you referring to subtracing 0.9R from 9.9R? because that's just subtracting one infinite series from another, which is a common way to deal with an infinite series.

you have some series: 0.9 + 0.09 + 0.009 + ... = 0.9R

when you add that to nine, you get 9.9R, so subtracting that from 9.9R would give you just 9.0. there's no "extra nine", the series is infinite but countable."

(/sarcasm) uh oh, you phrased the same thing in a slightly different way. That must mean you are right and i'm wrong. Look man, you can't subtract infinity from infinity and get 0. It isn't a constant. It's an abstract idea.

"its moronic to call someone moronic after half-understanding something that you half-read ;-)"

I'm not the one with a mis-understanding here. You are. Even Jp understands where i'm coming from now.

"I'm actually out of school, Solbadguy500. And I did do the highest level of maths available"

What was that? 1st year calculus is the highest we can go here.

I just don't think people can grasp the idea that one number can be next to another number with nothing in between them. The two are just as close to each other as physically possible. By the way, it might just be an australian thing, but how come you call it "maths?" O_o.