InfSum15.cpp

#include "pch.h"
#include <iostream>
#include <stdio.h>
#include <windows.h>
#include <math.h>

double myFact(int n);

int main()
{
	SetConsoleOutputCP(1251);
	SetConsoleCP(1251);

	int n = 1;
	double sum = 0, newSum = 0, first, fac, sn, e, x;

	printf("Введите x и e: \n");
	scanf_s("%lf%lf", &x, &e);

	printf("x ---- %.lf\n", x);
	printf("e ---- %.lf\n", e);

	while (1) {
		first = pow(-1, 2 * n + 1);
		printf("first: %.30f\n", first);
		sn = sin(n * x);
		printf("sn: %.30f\n", sn);
		fac = myFact(n + 3);
		printf("fac: %.30f\n", fac);
		newSum = first * sn / fac;
		printf("newSUM = %.30f\n", newSum);

		std::cout << "----------------" << abs(newSum - sum) << "\n";

		if (abs(newSum - sum) < e) {
			printf("Всё");
			break;
		}

		sum += newSum;

		n++;
	}

	printf("Сумма: %.30lf", newSum);

	return 0;
}


double myFact(int n) {
	double result = 1;
	if (n == 0) { return result; }
	for (int i = 1; i <= n; i++)
	{
		result *= i;
	}
	return result;
}