#include<stdio.h>
#include<math.h>
			  // NEWTON RAPHSON METHOD
float f(float x);
float f_(float x);
float abso(float x);

void main(void)
{
float x,xa,err;
printf("\nEnter the initial estimate of the root >  ");
scanf("%f",&x);
printf("\nEnter the allowed zero error in root of f(x) >   ");
scanf("%f",&err);
while(1)
	{
	xa=x-f(x)/f_(x);
	if(abso( f(xa) )<err)  break;
	else x=xa;
	}
printf("\nThe approx. root is: %f",xa);
}

float f(float x)
{
float temp;
temp=2*x*x-10;     // The function
return temp;
}

float f_(float x)
{
float temp;
temp=4*x;          // The derivative of function
return temp;
}

float abso(float x)
{
if(x<0)
	x=0-x;
return x;
}