C++ Program to print series using function: x + x^3/3! + x^5/5! +…..+ x^n/n!

What are Functions ?

Function is a block of statements that performs some operations. All C++ programs have at least one function – function called “main()”. This function is entry-point of your program.

A function declaration tells the compiler about a function’s name, return type, and parameters. A function definition provides the actual body of the function.

Defining a Function : :

The general form of a C++ function definition is as follows:

return_type Function_Name( list of parameters )
{
//function’s body
}

• return_type : suggests what the function will return. It can be void, int, char, some pointer or even a class object.
• Function_Name : is the name of the function, using the function name it is called.
• Parameters : are variables to hold values of arguments passed while function is called. A function may or may not contain parameter list.
• Function body : is he part where the code statements are written.

Below is the source code for C++ Program to print series using function: x + x^3/3! + x^5/5! +…..+ x^n/n! which is successfully compiled and run on Windows System to produce desired output as shown below :

SOURCE CODE : :

/*  C++ Program to print series using function: x + x^3/3! + x^5/5! +.....+ x^n/n! */

#include<iostream>
using namespace std;

double sum(int ,int );
double res;

int main()
{
    int x,n;

    cout<<"\nEnter value of x :: ";
    cin>>x;
    cout<<"\nEnter value of n :: ";
    cin>>n;

    res=sum(x,n);

    cout<<"\nSum of series [ x + x^3/3! + x^5/5! +.....+ x^n/n!] is :: [ "<<res<<" ]\n";

    return 0;
}

double sum(int a,int b)
{
    long power(int,int);
    int i,j;
    double s=0,fac=1;
    long p;

    for(i=1;i<=b;i+=2)
    {
    p=power(a,i);
    for(j=1;j<=i;++j)
    {
    fac*=j;
    }
    s+=p/fac;
    fac=1;
    }
    return(s);
}

long power(int x,int i)
{
    long res=1,j;
    for(j=1;j<=i;++j)
    {
    res*=x;
    }
    return(res);
}

OUTPUT : :

/*  C++ Program to print series using function: x + x^3/3! + x^5/5! +.....+ x^n/n! */

Enter value of x :: 5

Enter value of n :: 20

Sum of series [ x + x^3/3! + x^5/5! +.....+ x^n/n!] is :: [ 74.1779 ]

Process returned 0

Above is the source code for C++ Program to print series using function: x + x^3/3! + x^5/5! +…..+ x^n/n! which is successfully compiled and run on Windows System.The Output of the program is shown above .