I think I may be over-thinking this as I have had one formal course in QM and an independent study course in QM, but any help is MORE THAN GREATLY APPRECIATED!!! 1. The problem statement, all variables and given/known data Prove that |-V> = -|V> 2. Relevant equations He instructs us to begin with |V> + (-|V>) = 0|V> = |0> 3. The attempt at a solution Let -|V> = |W> Then |V> + |W> = 0|V> = |0> which implies that |W> = |-V> ? I'm really confused.