ACOS(3) BSD Library Functions Manual ACOS(3)
NAME
acos, acosf -- arc cosine function
LIBRARY
Math Library (libm, -lm)
SYNOPSIS
#include <math.h>
double
acos(double x);
float
acosf(float x);
DESCRIPTION
The acos() and acosf() functions compute the principal value of the arc cosine of x in the range [0, pi].
RETURN VALUES
If |x|>1, acos(x) and acosf(x) set the global variable errno to EDOM.
SEE ALSO
asin(3), atan(3), atan2(3), cos(3), cosh(3), math(3), sin(3), sinh(3), tan(3), tanh(3)
STANDARDS
The acos() function conforms to ANSI X3.159-1989 (``ANSI C89'').
BSD
May 2, 1991 BSD