4. Use the MATLAB command inv to find the inverse of the matrix A below. Then adjoin the identity matrix I = eye(3) to A to form the 3x6 matrix B = [A I]. Row-reduce using rref(B) to find the inverse of A again. What do you observe? [1 2 1; A = 3 7 10; 7 16 -2]
5. Using the same matrix A from problem 4 above, find the transpose of the matrix, A^T. The command for the transpose of a real matrix A is A'. Find the transpose of the matrix by hand. Does it match with MATLAB?
6. Let A and B be the 3x3 matrices below:
A = [2 4 1; 3 4 2; -4 12 2]
B = [3 1 2; 15 -4 12; -1 2 1]
a. Use MATLAB to find A^(-1)B^(-1), (AB)^(-1), and (BA)^(-1). What do you observe?
b. Use MATLAB to find (A^(-1))^T and (A^T)^(-1). What do you observe? Remember: You can obtain answers in rational form by using the rats command.