उत तर:
#A X B = 7i-17j-5k #
स पष ट करण:
# एक = a_i, a_j, a_k #
# ब = b_i, b_j, b_k #
#A X B = i (a_j * b_k-a_k * b_j) -j (a_i * b_k-a_k * b_i) + k (a_i * b_j-a_j * b_i) #
#thus; #
# एक = 9,4, -1 #
#B = - 1, -1,2 #
#A X B = i (4 * 2 - (- 1 * -1)) - j (9 * 2 - (- 1 * -1)) + k (-1 * 9-4 * -1) #
# ए एक स ब = आई (8-1) -ज (18-1) + क (-9 + 4) #
#A X B = 7i-17j-5k #