# ATANH

Returns the inverse hyperbolic tangent of a number. Number must be between -1 and 1 (excluding -1 and 1). The inverse hyperbolic tangent is the value whose hyperbolic tangent is *number*, so ATANH(TANH(number)) equals *number*.

## Syntax

```
ATANH(number)
```

### Parameters

Term | Definition |
---|---|

number | Any real number between 1 and -1. |

## Return value

Returns the inverse hyperbolic tangent of a number.

## Example

Formula | Description | Result |
---|---|---|

=ATANH(0.76159416) | Inverse hyperbolic tangent of 0.76159416 | 1.00000001 |

=ATANH(-0.1) | -0.100335348 | |