C++ program to get the Sum of series: 1 – x^2/2! + x^4/4! -…. upto nth term

In this tutorial, we will be discussing a program to get the sum of series 1 – x^2/2! + x^4/4! … upto nth term.

For this we will be given with the values of x and n. Our task will be to calculate the sum of the given series upto the given n terms. This can be easily done by computing the factorial and using the standard power function to calculate powers.

Example

#include <math.h>
#include <stdio.h>
//calculating the sum of series
double calc_sum(double x, int n){
double sum = 1, term = 1, fct, j, y = 2, m;
int i;
for (i = 1; i < n; i++) {
fct = 1;
for (j = 1; j <= y; j++) {
fct = fct * j;
}
term = term * (-1);
m = term * pow(x, y) / fct;
sum = sum + m;
y += 2;
}
return sum;
}
int main(){
double x = 5;
int n = 7;
printf("%.4f", calc_sum(x, n));
return 0;
}

Output

0.3469
Published on 03-Dec-2019 10:19:02