Question

Find the value of x given that A²  = B
A = `[(2, 12),(0 , 1)]` B = `[(4, x),(0, 1)]`

Answer 1

A = `[(2, 12),(0 , 1)]`
∴ A² = `[(2 , 12),(0, 1)][(2, 12),(0,1)]`
= `[(4 , 36),(0, 1)]`
∵ A² = B (given)
∴ `[(4, 36),(0, 1)] = [(4, x),(0, 1)]`
∴ x = 36.