#include <iostream>
#include <iomanip>
 
using namespace std;
 
double f(double x, double eps)
{
    double s = 3, p1 = 1, p2 = 2, t = 3;
    for(; abs(t) > eps;)
    {
        p2 *= -2*x;
        p1 *= x;
        s += (t = p1+p2);
    }
    return s;
}
 
 
int main(int argc, char * argv[])
{
    for(double x = 0; x < 0.45; x += 0.05)
    {
        cout << setw(5) << left << x << "  " << setw(7) << f(x,0.0001) << "  " << setw(7) << 3/(1-x)/(1+2*x) << endl;
    }
}
 

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