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

1 Answer
Douglas K.
Oct 2, 2016

5hati + 5hatj - 5hatk5ˆi+5ˆj−5ˆk

Explanation:

I use a 5 column matrix to compute the cross product:
|i....j.....k|i....j|
|3 -1....2|3 -1|
|1. -2. -1|1. -2|

= hati{(-1)(-1) - (2)(-2)} + hatj{(2)(1) - (3)(-1)} + hatk{(3)(-2)-(-1)(1)}=ˆi{(−1)(−1)−(2)(−2)}+ˆj{(2)(1)−(3)(−1)}+ˆk{(3)(−2)−(−1)(1)}

= 5hati + 5hatj - 5hatk=5ˆi+5ˆj−5ˆk

Related questions
See all questions in Vector Operations
Impact of this question
1222 views around the world
You can reuse this answer
Creative Commons License