Definition:Inverse Hyperbolic Tangent/Complex/Definition 1

Definition
The inverse hyperbolic tangent is a multifunction defined as:


 * $\forall z \in \C: \tanh^{-1} \left({z}\right) := \left\{{w \in \C: z = \tanh \left({w}\right)}\right\}$

where $\tanh \left({w}\right)$ is the hyperbolic tangent function.

Also see

 * Equivalence of Definitions of Inverse Hyperbolic Tangent