Question

 If A = `[(4, -4),(-3, 3)], B = [(2, 3),(-1, -2)], C = [(6, 5),(3, 0)]`, find AB.

Answer 1

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

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

= `[(8 + 4, 12 + 8),(-6 - 3, -9 - 6)]`

= `[(12, 20),(-9, - 15)]`