Let L1 and L2 be languages over ∑ = {a, b} represented by the regular expressions (a* + b)* and (a + b)* respectively.
Which of the following is true with respect to the two languages?
Solution
The correct answer is option 3.
Key Points
(a+b)* is a universal set grammer which can generate all strings over all possible alphabet "a"and"b".
(a* + b)*= a* can generate epsilon, and reamaining part is like (a + b)*
(a* + b)*=(a + b*)*=(a*b*)*=(a*+ b*)* =a*(ba*)*=b*(ab*)*=(a + b)* all grammers are equal.
∴ Hence the correct answer is L1 = L2.