easySine

/*Question 5: Write a C++ program with function ‘easySin()’ that takes a number ‘x’ as
input and calculates its simplified sine expansion series. The series expansion is
given below, and you must calculate first 10 values of the series using loop.
Sine Series:
Sin(x) = x – x/3 + x/5 – x/7 + x/9 – x/11 + x/13 – x/15 + x/17 – x/19
Expected output:
Input: x = 5
Output: Sin(5) = +5–5/3+5/5–5/7+5/9–5/11+5/13–5/15+5/17–5/19 = 3.8023
Print the whole series as well the result on screen as shown below.
*/

#include<iostream>
using namespace std;

void myIntro();
int input_number(void);
bool is_even(int);

float easySine(int);

int main()
{
    int x = 0;
    float sineExp = 0;
    cout << "To compute y=Sin(x), enter a value for x: ";
    x = input_number();
    sineExp = easySine(x);
    cout << "\nSine(5)=" << sineExp;
    //print_EasySine(x);
    return 0;
}

void myIntro(void)
{
    cout << "\nName: Muhammad Talha Dar";
    cout << "\nRegistration#: L1S19BSCS0060";
    cout << "\nSection: B";
    cout << "\n============================" << endl;
}

int input_number(void)
{
    int a = 0;
    cout << "\nEnter Number: ";
    cin >> a;
    return a;
}

bool is_even(int a)
{
    if (a % 2 == 0)
    {
        return 1;
    }
    else
    {
        return 0;
    }
}

float easySine(int x)
{
    int i = 1, z = 1;
    float sin = 0;
    while (i <= 10 && z <= 19)
    {
        if (is_even(i) == 1)
        {
            sin = (sin - (x / z)*1.0);
        }
        else
        {
            sin = (sin + (x / z)*1.0);
        }
        z = z + 2;
        i = i + 1;
    }
    return sin;
}