Primitive of Reciprocal of Hyperbolic Sine of a x by Square of Hyperbolic Cosine of a x

Theorem

 * $\ds \int \frac {\d x} {\sinh a x \cosh^2 a x} = \frac 1 a \ln \size {\tanh \frac {a x} 2} + \frac {\sech a x} a + C$