CSCI 301 Math Exercises # 5

CSCI 301 Math Exercises # 5

Use the pumping lemma to prove that each of the following languages is not regular.
1. {aibj | i ≥ j ≥ 0}
2. {a4n+5b3n+2 : n ≥ 0}
3. {aibjck | i = j or j = k}