Question

Given A = `[(3, -2),(-1, 4)]`, B = `[(6),(1)]`, C = `[(-4),(5)]` and D = `[(2),(2)].` Find : AB + 2C – 4D

Answer 1

AB = `[(3, -2),(-1, 4)][(6),(1)] = [(18 - 2),(-6 + 4)] = [(16),(-2)]`

2C = `2[(-4),(5)]=[(-8),(10)]`

4D = `4[(2),(2)]=[(8),(8)]`

Now, AB + 2C – 4D = `[(16),(-2)] + [(-8),(10)] - [(8),(8)]`

= `[(16 - 8 - 8),(-2 + 10 - 8)]`

= `[(0),(0)]`