1. Given vectors u = [ x,y,5] , v = [3,1,-4], and w = [7,7,7] , find x and y such that u x v = w .

2. What can be said about non-zero vectors u, v and w if (u x v) x w = 0 ?

3. Simplify each vector operation.

a) j x (-j)

b) (i x j) x k

c) ( i x j ) x k