Page 305 - IT-802_class_12
P. 305

bill_amount = (100 * 4.5)+(unit - 100) * 5.5;

                  else if(unit<=650)
                          bill_amount=(100 * 4.5)+(250 * 5.5)+(unit-350) * 7;
                  else
                          bill_amount=(100*4.5)+(250*5.5)+(300*7)+(unit-650)*9;
                  System.out.println("Bill amount = "+bill_amount);

                }
                }
                 Output:

                 Enter consumed unit :
                 258
                 Bill amount = 1319.0
             25.   To calculate the roots of a quadratic equation, write a program in Java. The Quadratic Formula employs the
                 letters "a," "b," and "c" from "ax  + bx + c," where "a," "b," and "c" are simply numbers; these are the "numerical
                                             2
                 coefficients" of the quadratic equation you must solve. For ax² + bx + c = 0, the value of x is given by:
                    −     b 2  −b ±   4ac
                 x =
                           a 2
                 The following is the nature of the equation:
                 "Roots are imaginary" If the value of d is negative (d < 0).

                 "Roots are real and uneven" If the value of d is positive (d > 0).
                 "Roots are equivalent" If the value of d is zero (d = 0).

             Ans. package com.mycompany.quadratic_equation;
                import java.util.*;
                public class Quadratic_equation

                {
                  public static void main(String[] args)
                  {
                          Scanner sc = new Scanner(System.in);

                          System.out.println("Enter the value of a");
                          int a = sc.nextint();
                          System.out.println("Enter the value of b");
                          int b = sc.nextint();
                          System.out.println("Enter the value of c");
                          int c = sc.nextint();
                          double d = math.sqrt(b * b - 4 * a * c);

                          double root1 = (-b + d) / (2 * a);
                          double root2 = (-b - d) / (2 * a);
                          if (d < 0)
                                 System.out.println("Roots are imaginary");

                          if (d > 0)

                                                                                                Practical Work  303
   300   301   302   303   304   305   306   307   308   309   310