ACOS(3) BSD Library Functions Manual ACOS(3)NAME
acos — arc cosine function
SYNOPSIS
#include <math.h>
double
acos(double x);
DESCRIPTION
The acos() function computes the principal value of the arc cosine of x
in the range [0, π].
SPECIAL VALUESacos(1) returns +0.
acos(x) returns a NAN and raises the "invalid" floating-point exception
for |x| > 1.
SEE ALSOsin(3), cos(3), tan(3), asin(3), atan(3), atan2(3), sinh(3), cosh(3),
tanh(3), math(3), matherr(3)STANDARDS
The acos() function conforms to ISO/IEC 9899:1999(E).
BSD November 14, 2002 BSD