asin() and asinf()

  #include <math.h>

  

  double asin(double x);

  

  float  asinf(float x);

  

asin() computes the principal value of the arc sine of x.

The arc sine sin^(-1)(x) of x in the range between -Pi/2 and Pi/2 if x is in the range -1 <= x <= 1. If x is not in this range, NAN is returned and errno is set to EDOM.

acos() and acosf(),

atan() and atanf(),

atan2() and atan2f(),

cos() and cosf(), and

tan() and tanf()