NAME
acos, acosf,
acosl —
arc cosine functions
SYNOPSIS
/* -lm */
#include <math.h>
double
acos(double
x);
float
acosf(float
x);
long double
acosl(long
double x);
DESCRIPTION
The
acos()
function computes the principal value of the arc cosine of
x in the range [0, pi]. The
acosf()
function is a single precision version of acos().
The
acosl()
function is an extended precision version of
acos().
RETURN VALUES
If |x|>1,
acos(x),
acosf(x) and
acosl(x) set the global
variable errno to EDOM.
SEE ALSO
asin(3), atan(3), atan2(3), cos(3), cosh(3), sin(3), sinh(3), tan(3), tanh(3)