(2j×3i).k=? My text book says the answer is -6. But how?
Here we have used the following properties
#vec A times vec B = -vec B times vec A# #hat i times hat j = hat k# #hat k cdot hat k = |hat k|^2=1#
You could of course also use the determinant form for the scalar triple product
but this will be an overkill for this problem.