In this Java tutorial, you will learn how to find the roots of quadratic equation with a sample code snippet.
How to find the roots of quadratic equation?
RUN CODE SNIPPETpublic class Main {
public static void main(String[] args) {
double a = 2, b = -5, c = 6;
double root1, root2;
double determinant = b * b - 4 * a * c;
if (determinant > 0) {
root1 = (-b + Math.sqrt(determinant)) / (2 * a);
root2 = (-b - Math.sqrt(determinant)) / (2 * a);
System.out.format("root1 = %.2f and root2 = %.2f", root1, root2);
}
else if (determinant == 0) {
root1 = root2 = -b / (2 * a);
System.out.format("root1 = root2 = %.2f;", root1);
}
else {
double real = -b / (2 * a);
double imaginary = Math.sqrt(-determinant) / (2 * a);
System.out.format("root1 = %.2f+%.2fi", real, imaginary);
System.out.format("\nroot2 = %.2f-%.2fi", real, imaginary);
}
}
}OUTPUT
root1 = 1.25+1.20i root2 = 1.25-1.20i
In the above program the, coefficients of a, b, c are set to 2, -5, 6.
The determinant is calculated using b^2-4ac.
The roots are calculated based on the determinant and to calculate the square root of a number we use the library function Math.sqrt().
