Код:
#include <iostream>
#include <cstdio>
using namespace std;
double sqRoot(double num, double answ, double eps)
{
if((answ*answ-num)<0)
{
if((num-answ*answ)<=eps) return answ;
else return sqRoot(num,(answ*answ+num)/(2*answ),eps);
}
else if((answ*answ-num)<=eps) return answ;
else return sqRoot(num,(answ*answ+num)/(2*answ),eps);
}
int main()
{
printf("%lf\n",sqRoot(4,2,0.01));
printf("%lf\n",sqRoot(5,2,0.01));
}