I am confused on several areas of this. First, this is so obvious I am finding it hard to prove. Second, what are some definitions, axioms, or lemmas of an ll(k) grammar that I can use to build up a contropositive argument that for any ambiguous grammar it cannot be an LL(k) for any k? I've found this to be my best approach. Feel free to answer as opening or as theoretically as felt necessary, this was poorly explained in lecture and quite frankly any addition theory or hints is appreciated.