asin - arc sine function


SYNOPSIS

       #include <math.h>

       double asin(double x);


DESCRIPTION

       The  asin() function calculates the arc sine of x; that is
       the value whose sine is x.  If x falls outside  the  range
       -1 to 1, asin() fails and errno is set.


RETURN VALUE

       The  asin()  function  returns the arc sine in radians and
       the value is mathematically defined to  be  between  -PI/2
       and PI/2 (inclusive).


ERRORS

       EDOM   x is out of range.


CONFORMING TO

       SVID 3, POSIX, BSD 4.3, ISO 9899


SEE ALSO

       acos(3), atan(3), atan2(3), cos(3), sin(3), tan(3)