1. The problem statement, all variables and given/known data I could prove a, trying b now. 2. Relevant equations The definition of the cross prod.? 3. The attempt at a solution https://www.dropbox.com/s/0sauaexkl4j2yko/proof_cross_prod.pdf?dl=0 I did not manage to get a scalar times v and a scalar times w. (No need to point this out.) This is not an assignment, so you can give me the answer right away (LaTeX because I like it). But please, just point my mistake so that I can hopefully learn something.