Regular Expression Model Practice Questions for GATE | TOC | Question-3

Question

Find the equivalent of the Regular Expression:

Comments

None

Answer 1

Here L1 = { epsilon, a, b, aa, ab, bb, aaa, aab, abb, bbb, aaaa, aaab, aabb, abbb, bbbb, aaaaa, aaaab, aaabb, aabbb, abbbb, bbbbb,....................... }.

L2 = { ab, aab, abb, aaab, aabb, abbb, aaaab, aaabb, aabbb, abbbb,.....................}.

L1 - L2 = {epsilon, a, b, aa, bb, aaa, bbb, aaaa, bbbb, aaaaa, bbbbb,...................} = a* + b*.

L2 - L1 = { }.

So, from above observation L2 - L1 = ϕ. 

Option D is correct.

 

 

Comments

Question is for L2-L1.

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alright, changed my answer