Math Question

[zero-impact]

Yesterday there was an interesting bonus question on my gr12 advanced functions test that I was unable to solve.

For which non-zero real number does, give a positive integer?

From what i can tell, giving it a positive real will give 0 and giving a negative will always give a negative.
Any thoughts?

[DtY]

You sure it wasn't a trick question?
As far as I can tell, it can be simplified to 0 where x>0, or -2 where x<0

[bbi5291]

When I read this, I thought to myself: "OMG, compsci.ca has LaTeX support! Yaaay!" Then I read the code for your post.
Anyway, I think your reasoning is sound... I see no way that this could ever be positive at all, let alone a positive integer.

[zero-impact]

Thank you, maybe I'm not crazy after all... O_O

[A.J]

Well, plug in x = k and x = -k (where k is a positive real number). You'll notice that when x = k, the expression yields 0, and when x = -k, the expression yields -2...

So you are right.

[zero-impact]

Well, I was right. But stupid me didn't write anything for the answer assuming there was actually some kind of tricksy answer... >.<

[andrew.]

You should always write an answer even if it's wrong unless you get marks deducted for wrong answers.

[Brightguy]

bbi5291 @ Sat Oct 24, 2009 10:37 pm wrote:

When I read this, I thought to myself: "OMG, compsci.ca has LaTeX support! Yaaay!"

I know how you feel, compsci.ca actually used to have LaTeX support. It was glorious.

[andrew.]

Why doesn't it now? LaTeX support would be great.

[Brightguy]

Probably because there isn't enough mathematical discussion to warrant it. I've been making an effort for years to change that but the fact remains this place is overrun by programmers.