#include "stdio.h"
#include "locale.h"
#include "math.h"



void main() {

    setlocale(LC_ALL, "rus");

    double x, eps, fx, n = 0, Sn = 1, s, a = -1;

    do {
        printf_s("Введите x, -1 < x < 1: ");
        scanf_s("%lf", &x);
        printf_s("Введите eps: ");
        scanf_s("%lf", &eps);
    } while ((fabs(x) >= 1) || (eps < 0) || (eps > 1));

    fx = sqrt(1 + x);
    s = Sn;

    while ((fabs(fx - s) > eps) && (n < 100000)) {
        n++;
        a *= -1;
        Sn *= (a*((2*n-1)*(2*n))/(4*n*n*((1-2*n)/(-(1-2*(n-1))))))*x;
        s += Sn;

    }


    printf("fx = %12.10lf\ns = %12.10lf\nn = %12.10lf", fx, s, n);

}