1. The problem statement, all variables and given/known data http://ocw.mit.edu/courses/electric...s-fall-2011/assignments/MIT6_003F11_sol01.pdf 2. Relevant equations None 3. The attempt at a solution To be honest, I don't think you can prove something is impossible with just a sentence or two. I don't see why we check x odd [n] and x left[n] at 0 and notice they are both 0. 1. Why do we think to examine those numbers? 2. What do them both being zero tell us?