cos
cosine function
You're viewing an older version of this page (#4003). View the current version.
INTERFACE
#include <math.h>
double cos ( double x )
long cosl ( long double x )
float cosf ( float x )
#include <complex.h>
double complex ccos(double complex z)
long double complex ccosl(long double complex z)
float complex ccosf(float complex z)DESCRIPTION
The cos function computes the cosine of x (measured in radians). It returns a value in the range of -1 to 1.
The complex cosine is defined by
(1)
Example 1
Workings
\code #include <stdio.h> #include <math.h> int main() { double x = 1.047198; double result = cos(x); printf("The cosine of %lf is %lf
", x, result); return 0; } \endcode
Solution
Output:
The cosine of 1.047198 is 0.500000
SPECIAL VALUES
cos ( 0 ) returns 1.
cos ( ∞ ) returns a NaN and raises the invalid floating-point exception.
SEE ALSO
sin, tan, asin, acos, atan, atan2, sinh, cosh, tanh
STANDARDS
The cos function conforms to ISO/IEC 9899:1999(E).