ASIN(3)                   (2017-09-15)                    ASIN(3)

     NAME
          asin, asinf, asinl - arc sine function

     SYNOPSIS
          #include <math.h>

          double asin(double x);
          float asinf(float x);
          long double asinl(long double x);

          Link with -lm.

     Feature Test Macro Requirements for glibc (see
     feature_test_macros(7)):

          asinf(), asinl():
              _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L
                  || /* Since glibc 2.19: */ _DEFAULT_SOURCE
                  || /* Glibc versions <= 2.19: */ _BSD_SOURCE ||
              _SVID_SOURCE

     DESCRIPTION
          These functions calculate the principal  value  of  the  arc
          sine of x; that is the value whose sine is x.

     RETURN VALUE
          On success, these functions return the  principal  value  of
          the  arc  sine  of  x in radians; the return value is in the
          range [-pi/2, pi/2].

          If x is a NaN, a NaN is returned.

          If x is +0 (-0), +0 (-0) is returned.

          If x is outside the range [-1, 1], a  domain  error  occurs,
          and a NaN is returned.

     ERRORS
          See  math_error(7)  for  information  on  how  to  determine
          whether an error has occurred when calling these functions.

          The following errors can occur:

          Domain error: x is outside the range [-1, 1]
               errno is set to EDOM.  An invalid floating-point excep-
               tion (FE_INVALID) is raised.

     ATTRIBUTES
          For an explanation of the terms used in  this  section,  see
          attributes(7).     allbox;    lbw24    lb    lb   l   l   l.

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     ASIN(3)                   (2017-09-15)                    ASIN(3)

          Interface Attribute Value  T{   asin(),   asinf(),   asinl()
          T}   Thread safety  MT-Safe

     CONFORMING TO
          C99, POSIX.1-2001, POSIX.1-2008.

          The variant returning double also conforms to SVr4,  4.3BSD,
          C89.

     SEE ALSO
          acos(3), atan(3), atan2(3), casin(3), cos(3), sin(3), tan(3)

     COLOPHON
          This page is part of release 5.10  of  the  Linux  man-pages
          project.   A  description  of the project, information about
          reporting bugs, and the latest version of this page, can  be
          found at https://www.kernel.org/doc/man-pages/.

     Page 2                       Plan 9             (printed 5/18/22)