Arccosine Logarithmic Formulation

Theorem
For any real number $x: -1 \le x \le 1$:


 * $\arccos x = \dfrac 1 i \map \ln {x + \sqrt {x^2 - 1} }$

where $\arccos x$ is the arccosine and $i^2 = -1$.

Proof
Assume $y \in \R$ such that $0 \le y \le \pi$.

Also see

 * Arcsine Logarithmic Formulation
 * Arctangent Logarithmic Formulation
 * Arccotangent Logarithmic Formulation
 * Arcsecant Logarithmic Formulation
 * Arccosecant Logarithmic Formulation