Hi
Can someone tell me where i have gone wrong in the following question?
Given that v=2i + 2j + k, w = 3i - j + k find a unit vector perpendicular to both v and w.
unit vector = {a x b}/{|a x b|}
| a x b |=
a x b = i(2 x 1 - 1 x -1)-j(2 x 1 - 1 x 3)+k(2 x -1 - 2 x 3)
=i(2+1)-j(2-3)+k(-2-6)
=3i+j-8k
therefore unit vector = (3i+j-8k)
answer says its (-3i-j+8k)
P.S