C#: Calculate the sum of the series [ x - x^3 + x^5 - x^7 + x^9 -.....]

C# Sharp For Loop: Exercise-24 with Solution

Write a program in C# Sharp to find the sum of the series [ x - x^3 + x^5 - x^7 + x^9 - ........].

Sample Solution:-

C# Sharp Code:

using System;  // Importing necessary namespace

public class Exercise24  // Declaration of the Exercise24 class
{  
    public static void Main()  // Main method, entry point of the program
    {
        double x, sum, ctr, p, term;  // Declaration of variables x, sum, ctr, p, term as double
        int i, n;  // Declaration of variables i and n as integers

        Console.Write("\n\n");  // Displaying new lines
        Console.Write("Calculate the sum of the series [ x - x^3 + x^5 - x^7 + x^9 - .....]:\n");  // Displaying the purpose of the program
        Console.Write("------------------------------------------------------------");  // Displaying a separator
        Console.Write("\n\n");  	

        Console.Write("Input the value of x :");  // Prompting the user to input the value of x
        x = Convert.ToInt32(Console.ReadLine());  // Reading the value of x entered by the user

        Console.Write("Input number of terms : ");  // Prompting the user to input the number of terms
        n = Convert.ToInt32(Console.ReadLine());  // Reading the number of terms entered by the user

        term = 1;  // Initializing term with 1
        sum = 0;   // Initializing sum with 0

        // Loop to calculate the sum of the series
        for (i = 1, p = 1; i < n + 1; i++)
        {
            ctr = Math.Pow(x, p);  // Calculating x raised to the power p
            sum = sum + ctr * term;  // Adding the current term to the sum
            term = term * (-1);  // Changing the sign of the term for the next iteration
            p = p + 2;  // Increasing power by 2 for the next iteration
        }

        // Displaying the result
        Console.Write("\nThe sum = {0}\nNumber of terms = {1}\nThe value of x = {2}\n", sum, n, x);
    }
}

Sample Output:

Calculate the sum of the series [ x - x^3 + x^5 - x^7 + x^9 - .....]:
------------------------------------------------------------

Input the value of x :Input number of terms : 
The sum = 410
Number of terms = 5
 The value of x = 2
 

Flowchart:

C# Sharp Code Editor:

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