Arccotangent Logarithmic Formulation

Theorem
For any real number $x$:


 * $\arccot x = \dfrac 1 2 i \, \map \ln {\dfrac {1 + i x} {1 - i x} }$

where $\arccot x$ is the arccotangent and $i^2 = -1$.

Proof
Assume $y \in \R$, $ -\dfrac \pi 2 \le y \le \dfrac \pi 2 $.

Also see

 * Arcsine Logarithmic Formulation
 * Arccosine Logarithmic Formulation
 * Arctangent Logarithmic Formulation
 * Arcsecant Logarithmic Formulation
 * Arccosecant Logarithmic Formulation