The cross product is a vector-vector operation that, unlike the dot product, yields another vector. The easiest way to compute the cross product is using a 3x3 determinant (one of the many applications of the determinant) where

and

are the vectors to be crossed and

,

, and

are the unit vectors along the

,

, and

axes:
It should be clear from the definition that the cross product is
not commutative and that, in fact, reversing the order simply negates the result:
Excercise 3-9. Determine the cross product

: