MATLAB Function Reference |

**Syntax**

**Description**

```
Y = acosh(X)
```

returns the inverse hyperbolic cosine for each element of `X`

.

The `acosh`

function operates element-wise on arrays. The function's domains and ranges include complex values. All angles are in radians.

**Examples**

Graph the inverse hyperbolic cosine function over the domain .

**Definition**

The hyperbolic inverse cosine can be defined as

**Algorithm**

`acosh`

uses FDLIBM, which was developed at SunSoft, a Sun Microsystems, Inc. business, by Kwok C. Ng, and others. For information about FDLIBM, see http://www.netlib.org.

**See Also**

acosd | acot |

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