Synopsis
float asinf(float x);
Description

asinf returns the principal value, in radians, of the inverse circular sine of val. The principal value lies in the interval [??, +?] radians.

If |x| > 1, errno is set to EDOM and asinf returns HUGE_VALF.

If x is NaN, asinf returns x. If |x| > 1, asinf returns NaN.