5. Let = {a, b, c). Let L be the language of all words containing any string s of a's and b's followed by a number of c's equal to length(s). L = {(a + b)"c" | n>= 1} = {ac, bc, aacc, abcc, back, bbcc, aaaccc, aabccc, abaccc, ...} Prove that L is nonregular by using the first version of the pumping lemma