sinh(3) — Subroutines
NAME
sinh, cosh, tanh, sinhcosh − Hyperbolic functions
LIBRARY
Math Library (libm.a)
SYNOPSIS
#include <math.h>
double sinh (double x);
float sinhf (float x);
double cosh (double x);
float coshf (float x);
double tanh (double x);
float tanhf (float x);
double sinhcosh (double x);
float sinhcoshf (float x);
STANDARDS
Interfaces documented on this reference page conform to industry standards as follows:
cosh(): XPG4
sinh(): XPG4
tanh(): XPG4
Refer to the standards(5) reference page for more information about industry standards and associated tags.
DESCRIPTION
The sinh() and sinhf() functions compute the hyperbolic sine of x. Both sinh(x) and sinhf(x) are defined as (exp(x) − exp(−x))/2.
The cosh() and coshf() functions compute the hyperbolic cosine of x. Both cosh(x) and coshf(x) are defined as (e∗∗x + e∗∗(−x))/2.
The tanh() and tanhf() functions compute the hyperbolic tangent of x. Both tanh(x) and tanhf(x) are defined as (e∗∗x − e∗∗(−x))/(e∗∗x + e∗∗(−x)).
The sinhcosh() and sinhcoshf() functions compute both the hyperbolic sine and hyperbolic cosine of x. Both sinhcosh(x) and sinhcoshf(x) are defined as sinh x + icosh x.
The following table describes function behavior in response to exceptional arguments:
| Function | Exceptional Argument | Routine Behavior |
| sinh(), sinhf() | |x|>ln(2 ∗ max_float) | Overflow |
| cosh(), coshf() | |x|>ln(2 ∗ max_float) | Overflow |
| sinhcosh(), sinhcoshf() | |x|>ln(2 ∗ max_float) | Overflow |
The following table lists boundary values used by these functions:
| Value Name | Data Type | Hexadecimal Value | Decimal Value |
| ln(2 ∗ max_float) | S_FLOAT | 42B2D4FC | 89.41599 |
| T_FLOAT | 408633CE8FB9F87E | 710.475860073943 |