C Program To Find The Root Of The Equation x*x-25 Using Bisection Method

/* C Program To Find The Root Of The Equation x*x-25 Using Bisection Method */


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

float f(float);
int main()
{
    float x0,x1,x2,y0,y1,y2,e;
    int i;

      printf("Enter the initial guess\n");
          scanf("%f%f",&x0,&x1);
       y0=f(x0);
       y1=f(x1);

       if((y0*y1)>0)
       {
           printf("Invalid guess.\n");
           exit(0);
       }
      printf("Enter the allowable error:\n");
          scanf("%f",&e);


      printf("f(x)=x*x-25\n");
      printf("-------------------------------------------------------\n");
      printf("i\tx0\tx1\ty0\ty1\tx2\ty2\n");
      printf("-------------------------------------------------------\n");
          i=0;
        while((x1-x0)/x1>e)
        {
            printf("%d\t%.3f\t%.3f\t%.3f\t%.3f\t%.3f\t%.3f\n",i,x0,x1,y0,y1,x2,y2);

            x2=(x0+x1)/2;
            y2=f(x2);
            if(y0*y0>0)
            {
                x0=x2;
                y0=y2;
            }
            else{
                x1=x2;
                y1=y2;
            }
            i++;

        }
        printf("-------------------------------------------------------\n");
        printf("The root is %.3f",x2);

        return 0;
}
   float f(float x)
   {
       return(x*x-25);
   }

Out Put:

Enter the initial guess
2
7
Enter the allowable error:
.01
f(x)=x*x-25
-------------------------------------------------------
i       x0      x1      y0      y1      x2      y2
-------------------------------------------------------
0       2.000   7.000   -21.000 24.000  0.000   0.000
1       4.500   7.000   -4.750  24.000  4.500   -4.750
2       5.750   7.000   8.063   24.000  5.750   8.063
3       6.375   7.000   15.641  24.000  6.375   15.641
4       6.688   7.000   19.723  24.000  6.688   19.723
5       6.844   7.000   21.837  24.000  6.844   21.837
6       6.922   7.000   22.912  24.000  6.922   22.912
-------------------------------------------------------
The root is 6.961