The problem statement, all variables and given/known data, relevant equations, and the attempt at a solution are all in the attached file. I was reading through Invitation to Discrete Mathematics and attempted to solve an exercise that involved a proof. I've typeset everything in LaTeX and made a PDF out of it so that it does not clutter the post. The proof seems somewhat incomplete to me, almost as if I hadn't proofed what I had to. Therefore, I would like someone to assess it for me. This is **not** homework. Thanks for your time.