cos, cosf, cosl – cosine function

USAGE
       #include <math.h>

       double cos(double x);
       float cosf(float x);
       long double cosl(long double x);

       Link with -lm.

DESCRIPTION
       The  cos()  function returns the cosine of x, where x is given in radi-
       ans.

RETURN VALUE
       The cos() function returns a value between -1 and 1.

CONFORMING TO
       SVr4, 4.3BSD, C99.  The float and long double variants are C99 require-
       ments.

SEE ALSO
       acos(3), asin(3), atan(3), atan2(3), ccos(3), sin(3), tan(3)