| COS(3) | Library Functions Manual | COS(3) | 
cos, cosf,
  cosl —
#include <math.h>
double
  
  cos(double
    x);
float
  
  cosf(float
    x);
long double
  
  cosl(long
    double x);
cos(), cosf(), and
  cosl() functions compute the cosine of
  x (measured in radians). A large magnitude argument may
  yield a result with little or no significance. For a discussion of error due
  to roundoff, see math(3).
cos() function returns the cosine value.
cos() function conforms to ANSI
  X3.159-1989 (“ANSI C89”).
cos() function appeared in
  Version 1 AT&T UNIX.
| September 2, 2019 | NetBSD 9.3 |