cos() - math.h

The C library function double cos(double x) returns the cosine of a radian angle x.

Syntax

double cos(double x)

Example

#include <stdio.h>
#include <math.h>

#define PI 3.14159265

int main ()
{
   double x, ret, val;

   x = 60.0;
   val = PI / 180.0;
   ret = cos( x*val );
   printf("The cosine of %lf is %lf degrees\n", x, ret);
   
   x = 90.0;
   val = PI / 180.0;
   ret = cos( x*val );
   printf("The cosine of %lf is %lf degrees\n", x, ret);
   
   return(0);
}

Output / Return Value

The cosine of 60.000000 is 0.500000 degrees
The cosine of 90.000000 is 0.000000 degrees

Limitations

Alternatives / See Also

Reference