#include <iostream>
#include <math.h>

using namespace std;

double f(double);
double Sec(double, double, double);

double f(double x){
	return log(x) - 5 * cos(x);
}

double Sec(double a, double b, double epsilon){
	double x1 = a;
	double x2 = b;
	double fb = f(b);
	while (abs(f(x2)) > epsilon){
		double mpoint = x2 - (x2 - x1) * fb / (fb - f(x1));
		x1 = x2;
		x2 = mpoint;
		fb = f(x2);
	}
	return x2;
}

int main(){
	cout << "Your function: ln(x) - 5cos(x) " << endl;
	cout << "a = 1, b = 8" << endl << endl;
	double a = 1;
	double b = a + 1;
	double eps = 0.00001;
	for (int i = 1; i <= 8; i++) {
		double y = Sec(a, b, eps);
		if (y >= a && y < b)
			cout << "x = " << y << endl;
		a++;
		b++;
	}
	system("pause");
	return 0;
}