Q:

# Write a program in C++ to find the sum of series 1 - X^2/2! + X^4/4!-.... upto nth term

Write a program in C++ to find the sum of series 1 - X^2/2! + X^4/4!-.... upto nth term

Sample Output:

Find the sum of the series 1 - X^2/2! + X^4/4!-....:
---------------------------------------------------------
Input the value of X: 3
Input the value for nth term: 4
term 1 value is: 1
term 2 value is: -4.5
term 3 value is: 3.375
term 4 value is: -1.0125
The sum of the above series is: -1.1375

#include <iostream>
#include <math.h>
using namespace std;

int main()
{
float x, sum, term, fct, y, j, m;
int i, n;
y = 2;

cout << "\n\n Find the sum of the series 1 - X^2/2! + X^4/4!-....:\n";
cout << "---------------------------------------------------------\n";
cout << " Input the value of X: ";
cin >> x;
cout << " Input the value for nth term: ";
cin >> n;
sum = 1;
term = 1;
cout << " term 1 value is: " << term << endl;
for (i = 1; i < n; i++)
{
fct = 1;
for (j = 1; j <= y; j++)
{
fct = fct * j;
}
term = term * (-1);
m = pow(x, y) / fct;
m = m * term;
cout << " term " << i + 1 << " value is: " << m << endl;
sum = sum + m;
y += 2;
}
cout << " The sum of the above series is: " << sum << endl;
}