Question Discussion & Solution

Given the language L = {ab, aa, baa}, which of the following strings are in L*?
1) abaabaaabaa

2) aaaabaaaa

3) baaaaabaaaab

4) baaaaabaa

Which of the following languages is/are regular?
L1: {wxwR ? w, x ? {a, b}* and ?w?, ?x? >0} wR is the reverse of string w

L2: {anbm ?m ? n and m, n?0

L3: {apbqcr ? p, q, r ? 0}