 Hello and welcome to the session. Let us understand the following problem today. Write minors and cofactors of the elements of following determinant. We have determinant with elements 1, 0, 4, 3, 5, minus 1, 0, 1 and 2. Now let us write the solution. Minor of A11 which is equal to M11 is equal to 5 minus 1, 1, 2 which is equal to 10 plus 1 which is equal to 11. Now, minor of A12 is equal to M12 which is equal to 3 minus 1, 0, 2 which is equal to 6 minus 0 which is equal to 6. Now, minor of A13 is equal to M13 which is equal to 3501 which is equal to 3 minus 0 which is equal to 3. Now, minor of A21 is equal to M21 which is equal to determinant 0, 4, 1, 2 which is equal to 0 minus 4 which is equal to minus 4. Minor of A22 is equal to M22 which is equal to determinant 1402 which is equal to 2 minus 0 which is equal to 2. Minor of A23 is equal to M23 which is equal to 1001 which is equal to 1 minus 0 which is equal to 1. Minor of A31 is equal to M31 which is equal to 0, 4, 5 minus 1 which is equal to 0 minus 20 which is equal to minus 20. Now, minor of A32 is equal to M32 which is equal to determinant 143 minus 1 which is equal to minus 1 minus 12 which is equal to minus 13. Now, last minor of A33 is equal to M33 which is equal to determinant 1035 which is equal to 5 minus 0 which is equal to 5. Now, let us find the co-factor. Co-factor of A11 is equal to A11 which is equal to minus 1 to the power 1 plus 1 M11 which is equal to minus 1 squared into 11 which is equal to 11. Now, co-factor of A12 is equal to A12 which is equal to minus 1 to the power 1 plus 2 M12 is equal to minus 1 cubed into 6 which is equal to minus 6. Now, co-factor of A13 is equal to A13 which is equal to minus 1 to the power 1 plus 3 M13 is equal to minus 1 to the power 4 into 3 which is equal to 3. Co-factor of A21 is equal to A21 which is equal to minus 1 to the power 2 plus 1 M21 which is equal to minus 1 to the power 3 into minus 4 which is equal to 4. Now, co-factor of A22 is equal to A22 which is equal to minus 1 to the power 2 plus 2 M22 which is equal to minus 1 to the power 4 into 2 which is equal to 2. Now, co-factor of A23 is equal to A23 which is equal to minus 1 to the power 2 plus 3 M23 which is equal to minus 1 to the power 5 into 1 which is equal to minus 1. Now, co-factor of A33 is equal to A33 is equal to minus 1 to the power 3 plus 3 M33 is equal to minus 1 to the power 6 into 5 which is equal to 5. Now, co-factor of A31 is equal to A31 which is equal to minus 1 to the power 3 plus 1 M31 which is equal to minus 1 to the power 4 into minus 20 which is equal to 20 minus 20. Now, last co-factor of A32 is equal to A32 is equal to minus 1 to the power 3 plus 2 M32 which is equal to minus 1 to the power 5 into minus 13 which is equal to 13. Now, the required answer is M11 is equal to 11, M12 is equal to 6, M13 is equal to 3, M21 is equal to minus 4, M22 is equal to 2, M23 is equal to 1, M31 is equal to minus 20, M32 is equal to minus 13, M33 is equal to 5. Similarly, co-factor now A11 is equal to 11, A12 is equal to minus 6, A13 is equal to 3, A21 is equal to 4, A22 is equal to 2, A23 is equal to minus 1, A31 is equal to minus 20, A32 is equal to 13 and A33 is equal to 5. This is our required answer. I hope you understood the problem. Bye and have a nice day.