Power Reduction Formulas/Hyperbolic Cosine Squared

Theorem

 * $\cosh^2 x = \dfrac {\cosh 2 x + 1} 2$

where $\cosh$ denotes hyperbolic cosine.

Also see

 * Square of Hyperbolic Sine
 * Cube of Hyperbolic Sine
 * Cube of Hyperbolic Cosine
 * Fourth Power of Hyperbolic Sine
 * Fourth Power of Hyperbolic Cosine