Primitive of Reciprocal of Square of 1 minus Cosine of a x

Theorem

 * $\ds \int \frac {\d x} {\paren {1 - \cos a x}^2} = \frac {-1} {2 a} \cot \frac {a x} 2 - \frac 1 {6 a} \cot^3 \frac {a x} 2 + C$

Also see

 * Primitive of $\dfrac 1 {\paren {1 - \sin a x}^2}$