- Write a C++ program to find the roots of a quadratic equation.

Any **quadratic equation** can be represented as ax2 + bx + c = 0, where a, b and c are constants( a can't be 0) and x is unknown variable.

For Example

2x2 + 5x + 3 = 0 is a quadratic equation where a, b and c are 2, 5 and 3 respectively.

To calculate the roots of quadratic equation we can use below formula. There are two solutions of a **quadratic equation**.

**x = (-2a + sqrt(D))/2
x = (-2a - sqrt(D))/2**
where, D is

**Discriminant**, which differentiate the nature of the

**roots of quadratic equation**.

## C++ Program to find all square roots of a quadratic equation

#include <iostream> #include <cmath> using namespace std; int main() { float a, b, c, determinant, root1, root2, real, imag; cout << "Enter coefficients a, b and c of quadratic equation ax^2 + bx + c = 0 \n"; cin >> a >> b >> c; /* Calculate determinant */ determinant = b*b - 4*a*c; if(determinant >= 0) { root1= (-b + sqrt(determinant))/(2 * a); root2= (-b - sqrt(determinant))/(2 * a); cout << "Square roots are " << root1 << " " << root2; } else { real= -b/(2*a); imag = sqrt(-determinant)/(2 * a); cout << "Square roots are " << real << "+" << imag << "i , " << real << "-" << imag << "i"; } return 0; }Output

Enter coefficients a, b and c of quadratic equation ax^2 + bx + c = 0 3 7 2 Roots of 3.00x^2 + 7.00x + 2.00 = 0 are -0.33 and -2.00