sem 1

#include <iostream>
#include <cmath>

double phi(double);
double psi(double);
double lamda(double);
double lamda_der(double);
double F(double, double);
double F_der(double, double);
double calculate(double, double);
void out(int, double);
int n_in();
double eps_in();

int main()
{
	out(n_in(), eps_in());

	return 0;
}

double eps_in()
{
	double eps;

	std::cout << "enter eps: ";
	std::cin >> eps;

	return eps;
}

int n_in()
{
	int n;

	std::cout << "enter n: ";
	std::cin >> n;

	return n;
}

double phi(double x)
{
	return .8*x*x - 3*x + 1.7;
}

double psi(double x)
{
	return (.3*x - 1)/sqrt(1 + x + x*x);
}

double lamda(double y)
{
	return y + log(1 + y*y);
}

double lamda_der(double y)
{
	return 1 + 2*y/(1 + y*y);
}

double F(double x, double y)
{
	return y*phi(x) + psi(x) + lamda(y);
}

double F_der(double x, double y)
{
	return psi(x) + lamda_der(y);
}

double calculate(double x, double eps)
{
	double y_n, y_n_1 = -psi(x)/phi(x);

	do
	{
		y_n = y_n_1 - F(x, y_n_1)/F_der(x, y_n_1);
		y_n_1 = y_n;
	} while (abs(y_n - y_n_1) > eps);

	return y_n;
}

void out(int n, double eps)
{
	std::cout << "enter x[i], 0 <= i < n\n\n";

	for (int i = 0; i < n; i++)
	{
		double x;
		std::cin >> x;

		std::cout << "( " << x << ", " << calculate(x, eps) << " )\n";
	}
}