#include <iostream>
#include <cmath>
using namespace std;

int main() {
	setlocale(LC_ALL, "Russian");
	double n, x, Ep, delta, frac, ans;
	cout << "Введите точность: " << endl;
	cin >> Ep;
	n = 1;
	x = sin(rand());
	ans = x;
	frac = x;
	while (abs(frac) > Ep) {
		delta = ((2 * n - 1) * (2 * n - 1) * x * x) / (2 * n * (2 * n + 1));
		frac = -frac * delta;
		ans += frac;
		n++;
	}
	cout << "x = " << x << endl;
	cout << "Сумма: " << ans << endl;
	cout << "Встроенная функция: " << log(x + sqrt(1 + x * x)) << endl;





	system("pause");
	return 0;

}