Who can solve the problem in c ++ (I will thank of course)

Обычное разложение синуса по ряду Тейлора. В инете миллион примеров.

 

#include <iostream>
#include <cmath>
using namespace std;
int factorial(int n)
{
if (n < 0) return 0;
if (n == 0) return 1;
int sum = 1;
for (int i = 1; i <= n; ++i)
{
sum *= i;
}
return sum;
}
double foo(int n, double x)
{
double sum = 0.0;
for (int i = 1; i <= n; ++i)
{
sum += (pow(-1, n - 1) * pow(x, 2 * n - 1)) / factorial(2 * n - 1);
}
return sum;
}
int main(int argc, char* argv[])
{
setlocale(LC_ALL, "russian");
const double PI = 3.14159265358979323846;
int n;
double x;
cout << "Введите x ( |x| <= Pi/2 ) : ";
do
{
cin >> x;
} while (x > (PI / 2) || x < -(PI / 2));
cout << "Введите n:";
cin >> n;
cout << "Res =" << foo(n, x) << endl;
return 0;
}

C

#include <iostream>

#include <cmath>

using namespace std;

int factorial(int n)

{

    if (n < 0) return 0;

    if (n == 0) return 1;

    int sum = 1;

    for (int i = 1; i <= n; ++i)

    {

        sum *= i;

    }

    return sum;

}

double foo(int n, double x)

{

    double sum = 0.0;

    for (int i = 1; i <= n; ++i)

    {

        sum += (pow(-1, n - 1) * pow(x, 2 * n - 1)) / factorial(2 * n - 1);

    }

    return sum;

}

int main(int argc, char* argv[])

{

    setlocale(LC_ALL, "russian");

    const double PI = 3.14159265358979323846;

    int n;

    double x;

    cout << "Введите x ( |x| <= Pi/2 ) : ";

    do

    {

        cin >> x;

    } while (x > (PI / 2) || x < -(PI / 2));

    cout << "Введите n:";

    cin >> n;

    cout << "Res =" << foo(n, x) << endl;

    return 0;

}