Primitive of Square of Hyperbolic Sine of a x over Hyperbolic Cosine of a x

Theorem

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