Solution for the above question are as follows -

Code :

import java.util.*;

public class Main {
// generateTruthTable function defination
public static void generateTruthTable(int n) {
// get total no of rows
int r = (int) Math.pow(2,n);
// for loop over rows
for (int i=0; i<r; i++) {
for (int j=n-1; j>=0; j--) {
// check the truth table condition
if ((i/(int) Math.pow(2, j))%2 == 0) {
System.out.print("T ");
} else {
System.out.print("F ");
}
}
// print new line
System.out.println();
}
}
public static void main(String[] args) {
// get input from user
Scanner sc = new Scanner(System.in);
System.out.print("Enter Positive Number: ");
int n = sc.nextInt();
// call to generateTruthTable function
generateTruthTable(n);
}
}

Code Screen Shot :
https://media.cheggcdn.com/media/d85/d8538825-2b34-4073-a878-a7bfd83539bc/phpszjHVz.png

Output :

1)https://media.cheggcdn.com/media/fe3/fe38a4ff-8429-4b63-aa07-f9225345aa0c/phpWP7De0.png

2)https://media.cheggcdn.com/media/73e/73ef339c-1290-46e0-9bf5-9bd2f7835806/phpQixsrc.png

3)https://media.cheggcdn.com/media/95d/95df3bca-d0ec-47a5-abed-83b0937632bd/php6CRkJC.png