---
name: "ccosh"
section: "3"
platform: "linux"
package: "man-pages"
version: "6.19-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux", "freebsd"]
url: "https://new.carta.tech/ccosh"
---

# ccosh(3)

complex hyperbolic cosine

## NAME

ccosh, ccoshf, ccoshl - complex hyperbolic cosine

## LIBRARY

Math library (*libm*, *-lm*)

## SYNOPSIS

```
#include <complex.h>
```

**double complex ccosh(double complex** *z***);** **float complex ccoshf(float complex** *z***);** **long double complex ccoshl(long double complex** *z***);**

## DESCRIPTION

These functions calculate the complex hyperbolic cosine of *z*.

The complex hyperbolic cosine function is defined as:

```
ccosh(z) = (exp(z)+exp(-z))/2
```

## STANDARDS

C11, POSIX.1-2008.

## HISTORY

glibc 2.1. C99, POSIX.1-2001.

## SEE ALSO

[**cabs**(3)](/cabs/3.md), [**cacosh**(3)](/cacosh/3.md), [**csinh**(3)](/csinh/3.md), [**ctanh**(3)](/ctanh/3.md), [**complex**(7)](/complex/7.md)