Arc sine

[Classification]

Mathematical library

[Syntax]

#include <math.h>

long double __far asinl(long double x); (C99)

[Return value]

Returns the arc sine (arcsine) of x. The returned value is in radian and in a range of [-π / 2, π / 2].

If x is not between [-1, 1], asinl returns a Not-a-Number (NaN) and sets macro EDOM to global variable errno.

[Description]

This function calculates the arc sine (arcsine) of x. Specify x as, -1 <= x <= 1.