# Java Program to Compute (a-b)3 where Value of a and b are Given

In the previous article we have discussed Java Program to Compute (a+b)3 where Value of a and b are Given

In this program we are going to see how to compute (a-b)3 where value of a and b are given by using Java programming language.

## Java Program to Compute (a-b)3 where Value of a and b are Given

The formula of (a – b)3 is given below.

(a – b)3 = a3 – b3 – 3a2b + 3ab2

Now we will convert this into a valid Java expression.

Let x= (a-b)3

=  a3 – b3 – 3a2b + 3ab2

= (a * a * a) – (b * b * b) – (3 * a * a * b) + (3 * a * b * b)

Example:

Suppose a=4 and b=2

Then
(a-b)3
=(a * a * a) - (b * b * b) - (3 * a * a * b) + (3 * a * b * b)
= (4*4*4)-(2*2*2)-(3*4*4*2)+(3*4*2*2)
= 8

Now let’s see different ways to compute (a-b)3.

### Method-1: Java Program to Compute (a-b)3 where Value of a and b are Given By Using Static Input Value

Approach:

• Declare and initialize two integer variables say a and b.
• By using the formula compute (a-b)3
• Print the result.

Program:

class Main
{
public static void main(String[] args)
{
//declare the first integer variable with an integer value
int a= 6;
System.out.println("a= " +a);
//declare the second integer variable with an integer value
int b= 4;
System.out.println("b= "+b);
//declare another integer variable and assigned the formulated value to it.
int c=(a*a*a)-(b*b*b)-(3*a*a*b)+(3*a*b*b);
System.out.println("(a-b)3= "+c);
}
}

Output:

a= 6
b= 4
(a-b)3= 8

### Method-2: Java Program to Compute (a-b)3 where Value of a and b are Given By Using User Input Value

Approach:

• Declare two integer variables say a and b.
• Take the value of a and b as user input by using Scanner class.
• Then By using the formula compute (a-b)3
• Print the result.

Program:

import java.util.Scanner;
class Main
{
public static void main(String[] args)
{
//create object of scanner class.
Scanner sc=new Scanner(System.in);
System.out.print("a= ");
int a= sc.nextInt();
//Take the first input from the user.
System.out.print("b= ");
//Take the second input from the user.
int b= sc.nextInt();
//declare another integer variable and assigned the formulated value to it.
int c=(a*a*a)-(b*b*b)-(3*a*a*b)+(3*a*b*b);
System.out.println("(a-b)3= "+c);
}
}

Output:

a= 10
b= 5
(a-b)3= 125

### Method-3: Java Program to Compute (a-b)3 where Value of a and b are Given By Using User Defined Method

Approach:

• Declare two integer variables say a and b.
• Take the value of a and b as user input by using Scanner class.
• Then call a user defined method say computeValue() and pass a and b as parameter.
• Then inside method by using the formula compute (a-b)3
• Print the result.

Program:

import java.util.Scanner;
class Main
{
public static void main(String[] args)
{
//create object of scanner class.
Scanner sc=new Scanner(System.in);
System.out.print("a= ");
//Take the first input from the user.
int a= sc.nextInt();
System.out.print("b= ");
//Take the second input from the user.
int b= sc.nextInt();
//call the function
computeValue(a,b);
}
//define the method
public static void computeValue(int a, int b)
{
//declare another integer variable and assigned the formulated value to it.
int c=(a*a*a)-(b*b*b)-(3*a*a*b)+(3*a*b*b);
System.out.println("(a-b)3= "+c);
}

}

Output:

a= 8
b= 10
(a-b)3= -8

Don’t miss the chance of Java programs examples with output pdf free download as it is very essential for all beginners to experienced programmers for cracking the interviews.

Related Java Programs: