#include<bits/stdc++.h>
using namespace std;
double a,b,c,eps,c1, e, x, m, M,x1;
int i,n,k;
bool u;
double f (double x)
{
    return pow(x,4)-2*pow(x,2)-3;
}

double f1(double x){
    return 4*pow(x,3)-4*x;
}


void tang(double a, double b, double eps, double m1, double m2) {
	int k5=0;double x,x1,c=0;
  c = (a * f(b) - b * f(a))/(f(b)-f(a));
	if (f(a)*f(c)>0) { x = b;
					   } else { x = a;
					                   }
	do {
	     x1=x;
	     x = x1 - f(x1)/f1(x1);
	     k5++;


  }while(((m1*pow((x-x1),2))/(2*m2))>=eps);
  cout << " c : " << fixed << setprecision(15) << x << "  f(c) : " << fixed << setprecision(15) << f(x) << "  n : " << k5 << endl;


}

int main(){
    a=-2; b=-1;
    cout<<"a : "<<a<<" "<<"   b : "<<b<<endl;
    m=pow(10,-15);

    eps=pow(10,-15);

    cout<<"tangenta aposteriori"<<endl;
    tang(a,b,eps,44,m);
    int a=1,b=2;
    cout<<"a : "<< a<<" "<<"   b : "<<b<<endl;
    cout<<"tangenta aposteriori"<<endl;
    //tang(1.5,b,eps,44,7.5);
    m=pow(10,-15);
    tang(a,b,eps,44,m);
    return 0;
}