FALSE POSITION REGULA FALSI PROGRAM IN C

FALSE POSITION 

REGULA FALSI PROGRAM IN C

#include<stdio.h>
#include<conio.h>
#include<math.h>
#define f(x) ((x*x*x)-(2*x)-5)

void main()
{
  float x1,x2,ep,x3;
  printf("Enter x1 and x2 :");
  scanf("%f%f",&x1,&x2);
  printf("\nEnter Ep value : ");
  scanf("%f",&ep);

  if((f(x1)*f(x2))>0)
    printf("Initial approximation os unsuitable :");
  do
  {
    x3=((x1*f(x1))-(x2*f(x1)))/(f(x2)-f(x1));
    if((f(x1)*f(x3))>0)
    {
      x2=x3;
      // f(x2)==f(x3);
    }
    else
    {
      x1=x3;
      // f(x1)==f(x3);
    }
  }
  while((fabs(x1-x2)>ep) && f(x3)!=0);
  printf("value of x3 : %f",x3);
  getch();

}