ASIN(3) MachTen Programmer’s Manual ASIN(3)

NAME
asin - arc sine function

SYNOPSIS
#include <math.h>

double
asin(double x)

DESCRIPTION
The asin() function computes the principal value of the arc sine of x. A
domain error occurs for arguments not in the range [-1, +1]. For a dis-
cussion of error due to roundoff, see math(3).

RETURN VALUES
The asin() function returns the arc sine in the range [-pi/2, +pi/2] ra-
dians. On the VAX, and Tahoe , if:

|x| > 1

the global variable errno is set to EDOM and a reserved operand fault
generated.

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

STANDARDS
The asin() function conforms to ANSI C3.159-1989 (‘‘ANSI C’’).

4.4BSD June 4, 1993 1