Updated: 2021/Dec/3
COS(3) Library Functions Manual COS(3) NAME cos, cosf, cosl - cosine function LIBRARY Math Library (libm, -lm) SYNOPSIS #include <math.h> double cos(double x); float cosf(float x); long double cosl(long double x); DESCRIPTION The 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). RETURN VALUES The cos() function returns the cosine value. SEE ALSO acos(3), asin(3), atan(3), atan2(3), cosh(3), math(3), sin(3), sinh(3), tan(3), tanh(3) STANDARDS The cos() function conforms to ANSI X3.159-1989 ("ANSI C89"). HISTORY A cos() function appeared in Version 1 AT&T UNIX. NetBSD 9.99 September 2, 2019 NetBSD 9.99