# ATANH function

ATANH returns the inverse hyperbolic tangent of a number.

## Syntax

ATANH (`number`)

This
function returns the inverse hyperbolic tangent of `number`,
which is the value whose hyperbolic tangent is Number. The Number
must be between -1 and 1 (excluding -1 and 1).

## Example

`=ATANH(0.76159416)` returns `0.76159416(1,approximately)`.

`=ATANH(-0.1)` returns `-0.1(-0.10034)`.