# Documentation/Calc Functions/IMCOSH Under construction. For now, see the system Help files.

IMCOSH

## Summary:

Returns the hyperbolic cosine of a complex number. The hyperbolic cosine of a complex number can be expressed by:

cosh(a+bi)=cosh(a)cos(b)+sinh(a)sin(b)i

## Syntax:

IMCOSH(Complex_number)

## Returns:

The result is presented in the string format and has the character "i" or "j" as an imaginary unit.

The function always returns a string representing a complex number. If the result is a complex number with one of its parts (a or b) equal to zero, that part is not displayed.

## Arguments:

Complex_number is a complex number whose hyperbolic cosine is to be calculated.

A complex number is a string expression resulting in the form "a+bi" or "a+bj", where a and b are numbers. If the complex number is actually a real number (b=0), then it can be either a string expression or a number value.

## Examples:

=IMCOSH("4-3i") returns -27.0349456030742-3.85115333481178i.

=IMCOSH(2) returns 3.76219569108363 as a string. The imaginary part is equal to zero, so it is not displayed in the result.

## ODF standard:

This function is part of the Open Document Format for Office Applications (OpenDocument) standard Version 1.2. (ISO/IEC 26300:2-2015)