Q9. Calculate the following products or explain why the product is not defined. 1 4 5 (a) 2 3 6 3 -1 .O (b) (c) [-3 1 2] (d) [-3 1 2]. Q10. Let A = 2 and B = 3 3 (a) Determine whether A + B and AB are defined. If so, check that (A + B) = AT + BT and (AB) = BT AT. (b) Find all matrices CE Mex2(F) such that CA = CB. Q11. Let Ro cos O - sino = sina cosa , a E R. Determine R. Rg. Simplify your answer as much as possible. Hint: If your answer is simple enough, you will be be able see that Ro Ry = RaRa very easily!]