ASIN(3) Library Functions Manual ASIN(3)

asin, asinf, asinl
arc sine function

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 in the range [-pi/2, +pi/2].

If |x|>1, asin(x), asinf(x), and asinl(x) return NaN and set the global variable errno to EDOM.

acos(3), atan(3), atan2(3), cos(3), cosh(3), math(3), sin(3), sinh(3), tan(3), tanh(3)

The asin() function conforms to ISO/IEC 9899:1999 (“ISO C99”).
January 29, 2013 NetBSD 9.2