Question

Let `A = [(2,4),(3,2)] , B = [(1,3),(-2,5)], C = [(-2,5),(3,4)]`   

Find AB

Answer 1

Matrix A has 2 columns. This number is equal to the number of rows in matrix B. Therefore, AB is defined as:

`AB = [(2,4),(3,2)][(1,3),(-2,5)]`

= `[(2(1)+4(-2), 2(3)+4(5)), (3(1)+2(-2), 3(3)+2(5))]`

= ` [(2-8, 6+20), (3-4, 9+10)] `

= `[(-6, 26), (-1, 19)]`