1. The problem statement, all variables and given/known data Can someone help me with this proof? I'm supposed to show that if a subspace S is contained in subspace V, then S perp contains V perp. 2. Relevant equations None, or the dimensions must add up, so S + S perp = some dimension N, and V + V perp equals the same dimension N, if S and V are both subspaces of N. 3. The attempt at a solution Am I supposed to show that the dimensions don't add up? Can anyone provide suggestions? Thanks.