/* Cosine.c: cosine function approximation      */
/*                                              */
/* author: Rainer Doemer                        */
/*                                              */
/* modifications:                               */
/* 10/02/05 RD  initial version                 */

#include <stdio.h>

/* main function */

int main(void)
{
    /* variable definitions */
    double x, y;

    /* input section */
    printf("Please enter real value x: ");
    scanf("%lf", &x);

    /* computation section */
    y = 1 - (x*x)/(2.0*1.0)
	  + (x*x*x*x)/(4.0*3.0*2.0*1.0)
	  - (x*x*x*x*x*x)/(6.0*5.0*4.0*3.0*2.0*1.0);

    /* output section */
    printf("cos(%f) is approximately %f\n", x, y);

    /* exit */
    return 0;
} /* end of main */

/* EOF */