Inverse Hyperbolic Cosecant

$\begin{figure}\begin{center}\BoxedEPSF{ArcCsch.epsf scaled 1000}\end{center}\end{figure}$

$\begin{figure}\begin{center}\BoxedEPSF{ArcCschReIm.epsf scaled 750}\end{center}\end{figure}$

The Inverse Function of the Hyperbolic Cosecant, denoted $\mathop{\rm csch}\nolimits ^{-1}x$ .