ACOSH(3) BSD Library Functions Manual ACOSH(3)NAME
acosh, acoshf — inverse hyperbolic cosine function
LIBRARY
Math Library (libm, -lm)
SYNOPSIS
#include <math.h>
double
acosh(double x);
float
acoshf(float x);
DESCRIPTION
The acosh() and acoshf() functions compute the inverse hyperbolic cosine
of the real argument x.
RETURN VALUES
If x is less than one, acosh(x) and acoshf(x) return NaN and set the
global variable errno to EDOM.
SEE ALSOasinh(3), atanh(3), exp(3), math(3)HISTORY
The acosh() function appeared in 4.3BSD.
BSD May 6, 1991 BSD