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

1 Answer
May 4, 2018

#(0, 18, 6)#

Explanation:

The easiest way to write out the cross product is as a determinant. This can be written as
#(1,-1,3) times (5,1,-3) = |(hati,hatj,hatk),(1,-1,3),(5,1,-3) | #

Calculating this,

#= hati(-1* -3 - 1 * 3) - hatj(1*-3-5*3) + hatk(1*1 - 5 * -1) #
#= - hatj(-3-15) + hatk(1 + 5) = 18hatj + 6hatk = (0,18,6) #