Tolong selesaikan no.5

5. Vektor
A (2, 1, -1)
B (3, 6 , -4)

2a - 3b = 2{(2, 1, -1)} -3 {3,6,-4)
2a - 3b = {(4, 2, -2) - (9,18,-12)}
2a - 3b = {(4-9),(2-18),(-2+12)}
2a - 3b = { -5, -16, 10)
atau = -5i -16j +10k