lab3_n2beta3

#include<math.h>
#include<iostream>
#define pi acos(-1.0)
using namespace std;
int main()
{
    setlocale(LC_ALL, "RUS");
    double x, b, h, a, y, i, s, e, p;
    e = 1.4e-1;
    b = pi;
    h = pi / 25;
    a = pi / 5;
    i = 1;
    x = a;
    s = (pow(-1, i) * cos(i * x)) / (i * i);
    p = (pow(-1, (i+1)) * cos((i+1) * (x+h))) / ((i+1) * (i+1));
    for (x = a; x <= b; x = x + h)
    {
        i++;
        p += (pow(-1, i) * cos(i * x)) / (i * i);
        if (fabs(p - s) > e)
        {
            s += (pow(-1, i) * cos(i * x)) / (i * i);
            continue;
        }
        else
        {
            break;
        }
        y = ((x * x) - ((pi * pi) / 3));
    }
        cout << "Сумма равна" << s;
    return 0;
}