(a) Show that the jth column of the matrix product A B is equal to the matrix...

Question:

(a) Show that the jth column of the matrix product A B is equal to the matrix product Abj, where bj is the jth column of B. It follows that the product AB can be written in terms of columns as
AB = [Ab1 Ab2 ˆ™ ˆ™ ˆ™ Abn].
(b) Show that the ith row of the matrix product AB is equal to the matrix product a,#, where a, is the ith row of A. It follows that the product AB can be written in terms of rows as