Let L be any formal language and it is given that L* is regular. Then select…

Let L be any formal language and it is given that L* is regular. Then select the correct statement about L.

Answer: C. L may or may not be regularExplanation: L may or may not be regular. Case 1: L is non-regular. For example, let L = {a^p | p is prime}. This is non-regular. Then L* = {a*} - {ϵ, a},…

  1. A.

     L must be regular

  2. B.

     L must be non-regular

  3. C.

    L may or may not be regular

  4. D.

    L must be finite

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Correct answer: C

Explanation:

L may or may not be regular.

Case 1: L is non-regular. For example, let L = {a^p | p is prime}. This is non-regular. Then L* = {a*} - {ϵ, a}, which is regular.

Case 2: L is regular. For example, let L = {a}. This is regular (finite). Then L* = a* is also regular.

Thus, if L* is regular, L can be either regular or non-regular. Therefore, L may or may not be regular.

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