Primitive of Power of Tangent of a x

Theorem

 * $\displaystyle \int \tan^n a x \ \mathrm d x = \frac {\tan^{n - 1} a x} {\left({n - 1}\right) a} - \int \tan^{n - 2} a x \ \mathrm d x + C$

Also see

 * Primitive of $\cot^n a x$