回答:
#AXB = -4i-13j-5k#
説明:
#vec A = 3,1、-5#
#vec B = 2、-1,1#
#A_x = 3#
#A_y = 1#
#A_z = -5#
#B_x = 2#
#B_y = -1#
#B_z = 1#
#AXB (A_y * B_z A_z * B_y)i (A_x * B_z A_z * B_x)j (A_x * B_y A_y B_x)k#
#AXB = i(1 * 1 - (5 * 1)) - j(3 * 1 + 2 * 5)+ k(-1 * 3-2 * 1)#
#AXB = i(1-5)-j(3 + 10)+ k(-3-2)#
#AXB = -4i-13j-5k#