# ACOSH

Returns the inverse hyperbolic cosine of a number. The number must be greater than or equal to 1. The inverse hyperbolic cosine is the value whose hyperbolic cosine is number, so ACOSH(COSH(number)) equals number.

## Syntax

ACOSH(number)


### Parameters

Term Definition
number Any real number equal to or greater than 1.

## Return value

Returns the inverse hyperbolic cosine of a number.

## Remarks

This function is not supported for use in DirectQuery mode when used in calculated columns or row-level security (RLS) rules.

## Example

Formula Description Result
= ACOSH(1) Inverse hyperbolic cosine of 1. 0
= ACOSH(10) Inverse hyperbolic cosine of 10. 2.993228