1. The problem statement, all variables and given/known data Prove that the additive identity in a vector space is unique 2. Relevant equations Additive identity There is an element 0 in V such that v + 0 = v for all v in V 3. The attempt at a solution Assume that the additive identity is NOT unique, then there exists y, z belong to V such that A + y = A + z = A, then y = z = 0, which is a contradiction. Is this enough to prove??