# Integral question

1. Nov 14, 2004

$$\int \sqrt{tan(x)} dx$$

this problem has me stumped. any suggestions would be greatly appreciated. thanks

2. Nov 14, 2004

### devious_

I remember doing this a while back. It's pretty long-winded. Anyway, here's a push in the right direction:

Use the substitution $u=\sqrt{\tan(x)}$, then:
$$u^2=\tan(x)[/itex] [tex]2u\,du=\sec^2(x)\,dx$$
$$2u\,du=1+\tan^2(x)\,dx$$
$$dx = \frac{2u}{1+u^4}\,du$$