/* --------------------------------- */
/* save as c3f.c                     */
/* --------------------------------- */
#include "x_hfile.h"
#include      "ff.h"
/* --------------------------------- */
int main(void)
{
   int                  n = 6;
double FirstApproximation = -0.8;

 clrscrn();
 
 printf(" Use Newton's method to approximate \n" 
        " the intersection point of :\n\n" 
        " g : x-> %s              and\n"
        " h : x-> %s\n\n\n" 
        " On a graph, you can see that, the intersection \n" 
        " point is between -1.0 and 0.0.\n\n" 
        " Choose x = %.1f as a first approximation.\n\n"
          , geq, heq, FirstApproximation);
 stop();

 clrscrn();
 printf(" In fact we want find x**2 = cos(x) or x**2 - cos(x) = 0\n\n" 
        " We want find the root of\n\n" 
        " f : x-> %s\n\n", feq);
 
 printf(" As a first approximation x = %.1f \n\n",FirstApproximation);
 printf(" The Newton's method give :                \n\n");
 p_Newton_s_Method(FirstApproximation, n, f, Df);


 Newton_s_Method(FirstApproximation, n, f, Df);
                        
 printf(" f(%.15f) = %.15f\n\n",  
              Newton_s_Method(FirstApproximation, n, f, Df)
           ,f(Newton_s_Method(FirstApproximation, n, f, Df)));

 stop();

 return 0;
}