Java Program to Find Inverse of a Matrix

Here you will get java program to find inverse of a matrix of order 2×2 and 3×3. We can find inverse of a matrix in following way. First find the determinant of matrix. Calculate adjoint of matrix. Finally divide adjoint of matrix by determinant. Image Source Below I have shared program to find inverse of 2×2 and 3×3 matrix. Java Program to Find Inverse of a Matrix 2×2 Matrix

import java.util.Scanner;

public class JavaMatrixInverse {
	public static void main(String args[]) {
		int i, j;
		float det, temp;
		float mat[][] = new float[2][2];
		
		Scanner sc = new Scanner(System.in);
		
		System.out.println("Enter elements of matrix row wise:");
		for(i = 0; i < 2; ++i)
			for(j = 0; j < 2; ++j)
				mat[i][j] = sc.nextFloat();
		
		det = (mat[0][0] * mat[1][1]) - (mat[0][1] * mat[1][0]);
		
		System.out.println("\ndeterminant = " + det);
		
		temp = mat[0][0];
		mat[0][0] = mat[1][1];
		mat[1][1] = temp;
		
		mat[0][1] = - mat[0][1];
		mat[1][0] = - mat[1][0];
		
		System.out.println("\nInverse of matrix is:");
		for(i = 0; i < 2; ++i) {
			for(j = 0; j < 2; ++j)
				System.out.print((mat[i][j]/det) + " ");
			
			System.out.print("\n");
		}
	}
}

import java.util.Scanner;

public class JavaMatrixInverse {

public static void main(String args[]) {

int i, j;

float det, temp;

float mat[][] = new float[2][2];

Scanner sc = new Scanner(System.in);

System.out.println("Enter elements of matrix row wise:");

for(i = 0; i < 2; ++i)

for(j = 0; j < 2; ++j)

mat[i][j] = sc.nextFloat();

det = (mat[0][0] * mat[1][1]) - (mat[0][1] * mat[1][0]);

System.out.println("\ndeterminant = " + det);

temp = mat[0][0];

mat[0][0] = mat[1][1];

mat[1][1] = temp;

mat[0][1] = - mat[0][1];

mat[1][0] = - mat[1][0];

System.out.println("\nInverse of matrix is:");

for(i = 0; i < 2; ++i) {

for(j = 0; j < 2; ++j)

System.out.print((mat[i][j]/det) + " ");

System.out.print("\n");

}

Output Enter elements of matrix row wise: 4 7 2