回答:
#A X B = 4i-10j-18k#
説明:
#A = i + 4j-2k#
#B = 3i-6j + 4k#
#AXB 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))#
#AXB = i(4 * 4 - (( - 2)*( - 6))) - j(1 * 4 - (3 *( - 2))+ k(1 *( - 6) - (3 * 4) ))#
#A X B = i(16-12)-j(4 + 6)+ k(-6-12)#
#A X B = i(4)-j(10)+ k(-18)#
#A X B = 4i-10j-18k#