What is the cross product of #(1,3,4) xx (-1,0,-1)#?

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Answer 1 · 2018-05-11T03:28:07

#(1,3,4) xx (-1,0,-1) = (-3,-3,3)#

#(1,3,4) xx (-1,0,-1)#

Can be written as a determinant:

#(1,3,4) xx (-1,0,-1) =| (hati,hatj,hatk), (1,3,4), (-1,0,-1) |#

Subtract the product of the minor diagonals from the product of the major diagonals:

#(1,3,4) xx (-1,0,-1) = {(3)(-1)-(4)(0)}hati+{(4)(-1)-(1)(-1)}hatj+{(1)(0)-(3)(-1)}hatk#

#(1,3,4) xx (-1,0,-1) = -3hati-3hatj+3hatk#

Change notation:

#(1,3,4) xx (-1,0,-1) = (-3,-3,3)#