Automata Theory Homework - Problem 4

Problem 4 (30): Prove that the following languages are not regular. (a) L = {a" b" c" | n 2 0} (b) L2 = {WWW,WR {a, b} and wp is the reversal of w} (c) La = {w we {a, b}" and the number of a's is greater than the number of b's}