# Java program to find Determinant of a Matrix

Write a Java program to find the Determinant of a 2 * 2 Matrix and 3 * 3 Matrix. The mathematical formula to find this Matrix determinant is as shown below.

## Java program to find Determinant of a 2 * 2 Matrix

It is an example to find the Determinant of a 2 * 2 Matrix. This Java code allows user to enter the values of 2 * 2 Matrix using the For loop. Next, we used the mathematical formula to find the matrix determinant.

```import java.util.Scanner;

public class DeterminantOfMatrix {
private static Scanner sc;

public static void main(String[] args) {
int[][] arr = new int[2][2];

int i, j, determinant = 0;

sc= new Scanner(System.in);

System.out.println("\n Please Enter the Matrix Items :  ");
for(i = 0; i < 2; i++) {
for(j = 0; j < 2; j++) {
arr[i][j] = sc.nextInt();
}
}

determinant = (arr[0][0] * arr[1][1]) - (arr[0][1] * arr[1][0]);

System.out.println("The Determinant of 2 * 2 Matrix = " + determinant );

}
}```

### Java 3 * 3 Matrix Determinant

This Java code finds the determinant of a 3 * 3 matrix. So, this Java example allows the users to enter the 3 * 3 matrix items. Please refer to C program to find Matrix Determinant article to understand this determinant code’s analysis in iteration wise.

```import java.util.Scanner;

public class DeterminantOfMatrix {
private static Scanner sc;

public static void main(String[] args) {
int[][] arr = new int[3][3];

int i, j, x, y, z, determinant = 0;

sc= new Scanner(System.in);

System.out.println("\n Please Enter the Matrix Items :  ");
for(i = 0; i < 3; i++) {
for(j = 0; j < 3; j++) {
arr[i][j] = sc.nextInt();
}
}

x = (arr[1][1] * arr[2][2]) - (arr[2][1] * arr[1][2]);
y = (arr[1][0] * arr[2][2]) - (arr[2][0] * arr[1][2]);
z = (arr[1][0] * arr[2][1]) - (arr[2][0] * arr[1][1]);

determinant = (arr[0][0] * x)- (arr[0][1] * y) + (arr[0][2] * z);

System.out.println("The Determinant of 3 * 3 Matrix = " + determinant );

}
}```

Java matrix Determinant output

`````` Please Enter the Matrix Items :
10 20 30
40 50 60
70 80 90
The Determinant of 3 * 3 Matrix = 0``````