@c ----------------------------------------------------------------------
@node asin, math
@subheading Syntax

@example
#include <math.h>

double asin(double x);
@end example

@subheading Description

This function returns the angle in the range @code{[-Pi/2..Pi/2]} whose
sine is @var{x}.

@subheading Return Value

The inverse sine, in radians, of @var{x}.  If the absolute value of
@var{x} is greater than 1, the return value is @code{NaN} and
@code{errno} is set to @code{EDOM}.

@subheading Portability

@portability ansi, posix