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     SIN(3M)                                                   SIN(3M)

     NAME
          sin, cos, tan, asin, acos, atan, atan2 - trigonometric
          functions

     SYNOPSIS
          #include <math.h>

          double sin(x)
          double x;

          double cos(x)
          double x;

          double asin(x)
          double x;

          double acos(x)
          double x;

          double atan(x)
          double x;

          double atan2(x, y)
          double x, y;

     DESCRIPTION
          Sin, cos and tan return trigonometric functions of radian
          arguments.  The magnitude of the argument should be checked
          by the caller to make sure the result is meaningful.

          Asin returns the arc sin in the range -π/2 to π/2.

          Acos returns the arc cosine in the range 0 to π.

          Atan returns the arc tangent of x in the range -π/2 to π/2.

          Atan2 returns the arc tangent of x/y in the range -π to π.

     DIAGNOSTICS
          Arguments of magnitude greater than 1 cause asin and acos to
          return value 0; errno is set to EDOM.  The value of tan at
          its singular points is a huge number, and errno is set to
          ERANGE.

     BUGS
          The value of tan for arguments greater than about 2**31 is
          garbage.