NAME

asin, asinf, asinl —

arc sine functions

LIBRARY

Math Library (libm, -lm)

#include <math.h>

double
asin(double x);

float
asinf(float x);

long double
asinl(long double x);

The asin(), asinf(), and asinl() functions compute the principal value of the arc sine of x.

These functions return the arc sine in the range [-pi/2, +pi/2] radians. If:

|
x
| > 1

asin(x) raises an invalid exception and returns an NaN.

The asin(), asinf(), and asinl() functions conform to ISO/IEC 9899:1999 (“ISO C99”).