java桌面应用程序

Question

设计一款求解一元二次方程的桌面应用程序 开发工具:Netbeans 8.2+jdk1.8
封装方程根信息的 Java Bean:
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Answer 1

import java.util.Scanner;

public class QuadraticEquation {
    private double a;
    private double b;
    private double c;

    public QuadraticEquation(double a, double b, double c) {
        this.a = a;
        this.b = b;
        this.c = c;
    }

    public double getA() {
        return a;
    }

    public double getB() {
        return b;
    }

    public double getC() {
        return c;
    }

    public double getDiscriminant() {
        return Math.pow(b, 2) - 4 * a * c;
    }

    public double getRoot1() {
        if (getDiscriminant() < 0) {
            return 0;
        } else {
            return (-b + Math.sqrt(getDiscriminant())) / (2 * a);
        }
    }

    public double getRoot2() {
        if (getDiscriminant() < 0) {
            return 0;
        } else {
            return (-b - Math.sqrt(getDiscriminant())) / (2 * a);
        }
    }
}

public class QuadraticEquationTest {
    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);
        System.out.print("Enter a, b, c: ");
        double a = input.nextDouble();
        double b = input.nextDouble();
        double c = input.nextDouble();

        QuadraticEquation equation = new QuadraticEquation(a, b, c);
        double discriminant = equation.getDiscriminant();

        if (discriminant > 0) {
            System.out.println("The roots are " + equation.getRoot1() + " and " + equation.getRoot2());
        } else if (discriminant == 0) {
            System.out.println("The root is " + equation.getRoot1());
        } else {
            System.out.println("The equation has no real roots");
        }
    }
}