Question

JAVA

Quadratic Equation

Design and write a Java code that solves a quadratic equation ??² + ?? + ? = 0. Please use class and object definitions and do not use procedural style.

Let the roots of ??² + ?? + ? = 0 be ? and ?.

Show that the following:

? + ? = − ?/?' ,

and

?? = ?/?' ,

for non-trivial of values of ?, ?, ?. Make sure that you address that complex numbers as objects.

Answer 1

//Java program

import java.util.Scanner;

class Complex{
   private double real,imag;
  
   public Complex(double r , double i) {
       real = r;
       imag = i;
   }
   public void setReal(double r) {
       real = r;
   }
   public void setImag(double i) {
       imag = i;
   }
   public double getReal() {
       return real;
   }
   public double getImag() {
       return imag;
   }
   public String toString() {
       return real + " + "+imag+ "i\n";
   }
}

class Quadratic{
   private double a,b,c;
  
   public Quadratic(double a,double b,double c) {
       this.a = a;
       this.b = b;
       this.c = c;
   }
   public double discriminate() {
       return b*b - 4*a*c;
   }
  
   public Complex getRoot1() {
       double D = discriminate();
       double real,imag;
       if(D<0) {
           real = (b*-1)/(2*a);
           imag = Math.sqrt(D*-1)/(2*a);
           return new Complex(real,imag);
          
       }
      
       real = (b*-1 + Math.sqrt(D))/(2*a);
       return new Complex(real,0);
   }
  
   public Complex getRoot2() {
       double D = discriminate();
       double real,imag;
       if(D<0) {
           real = (b*-1)/(2*a);
           imag = Math.sqrt(D*-1)/(2*a);
           return new Complex(real,imag);
          
       }
      
       real = (b*-1 - Math.sqrt(D))/(2*a);
       return new Complex(real,0);
   }
}

public class QuadraticEquation {
   public static void main(String args[]) {
       Scanner in = new Scanner(System.in);
      
       Quadratic q;
       double a,b,c;
       System.out.print("Enter a : ");
       a = in.nextDouble();
      
       System.out.print("Enter b : ");
       b = in.nextDouble();
      
       System.out.print("Enter c : ");
       c = in.nextDouble();
      
       q = new Quadratic(a,b,c);
      
       System.out.print("Root1 : "+ q.getRoot1());
       System.out.print("Root1 : "+ q.getRoot2());
      
       in.close();
      
   }
}

Answer 2