What is the cross product of #[3,1,-5]# and #[2, -1, 1] #?

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Answer 1 · 2016-05-12T21:29:16

#AXB=-4i-13j-5k#

#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#