What substitution can be used to solve this integral?

[Bazzinga]

So I've gotten the integral that I'm doing now down to:

int(cos(x)/sin^2(x) dx)

I looked it up on one of those online integral calculators to get me on the right track, and the answer is:

-1/sin(x)

It seems so simple, what am I missing?

 

[Mark44]

An ordinary substitution will do here: u = sin(x), du = cos(x)dx. Then your integral is
$$\int \frac{du}{u^2} = \int u^{-2}du$$