osx man page for cos

COS(3)							   BSD Library Functions Manual 						    COS(3)

NAME
     cos -- cosine function

SYNOPSIS
     #include <math.h>

     double
     cos(double x);

     long double
     cosl(long double x);

     float
     cosf(float x);

DESCRIPTION
     The cos() function computes the cosine of x (measured in radians).

SPECIAL VALUES
     cos(+-0) returns 1.

     cos(+-infinity) returns a NaN and raises the "invalid" floating-point exception.

VECTOR OPERATIONS
     If you need to apply the cos() function to SIMD vectors or arrays, using the following functions provided by the Accelerate.framework may
     give significantly better performance:

     #include <Accelerate/Accelerate.h>

     vFloat vcosf(vFloat x);
     vFloat vsincosf(vFloat x, vFloat *c);
     void vvcosf(float *y, const float *x, const int *n);
     void vvcos(double *y, const double *x, const int *n);
     void vvsincosf(float *s, float *c, const float *x, const int *n);
     void vvsincos(double *s, double *c, const double *x, const int *n);

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

STANDARDS
     The cos() function conforms to ISO/IEC 9899:2011.

BSD
								 December 11, 2006							       BSD