# Section (3) sinh

Section 3 Linux manual pages

## Name

sinh, sinhf, sinhl — hyperbolic sine function

## Synopsis

`#include <math.h>`
 ```double sinh(``` double x`)`;

 ```float sinhf(``` float x`)`;

 ```long double sinhl(``` long double x`)`; Note
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
`sinhf`(), `sinhl`():
`_ISOC99_SOURCE` || `_POSIX_C_SOURCE` >= 200112L || /* Since glibc 2.19:
*/ `_DEFAULT_SOURCE` || /* Glibc versions <= 2.19:
*/ `_BSD_SOURCE` || `_SVID_SOURCE`
Note Link with `−lm`.

## DESCRIPTION

These functions return the hyperbolic sine of `x`, which is defined mathematically as:

```    sinh(x) = (exp(x) − exp(−x)) / 2
```

## RETURN VALUE

On success, these functions return the hyperbolic sine of `x`.

If `x` is a NaN, a NaN is returned.

If `x` is +0 (−0), +0 (−0) is returned.

If `x` is positive infinity (negative infinity), positive infinity (negative infinity) is returned.

If the result overflows, a range error occurs, and the functions return `HUGE_VAL`, `HUGE_VALF`, or `HUGE_VALL`, respectively, with the same sign as `x`.

## ERRORS

See math_error(7) for information on how to determine whether an error has occurred when calling these functions.

The following errors can occur:

Range error: result overflow

`errno` is set to ERANGE. An overflow floating-point exception (`FE_OVERFLOW`) is raised.

## ATTRIBUTES

For an explanation of the terms used in this section, see attributes(7).

 Interface Attribute Value `sinh`(), `sinhf`(), `sinhl`() Thread safety MT-Safe

## CONFORMING TO

C99, POSIX.1-2001, POSIX.1-2008.

The variant returning double also conforms to SVr4, 4.3BSD, C89.

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