Question 5 (15 points) 2 4 6/ Let A = 3 15 B = 1 2 3 5). a) Find AT,BT, A - B.(A + B)", ATB, BA if they exist. b) Is the following inequality always true: CD # DC ? Give an example. c) If the matrix product CD exists, does the following equality always holds: (CD) = DTCT ? Give an example