#virtualgate

Question

Comments

D?? is it correct??

Not getting any clue thought over it for almost 20 minutes! it might be simple but not able to think in the correct way!!

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What is the answer given??

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which option according to you is correct??Verma Ashish

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It's very difficult to eliminate given options by choosing counter example...

If you get any counter example which eliminates some options then please share..

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@Verma Ashish

@Utkarsh Joshi

they have given d as the answer

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okay! :)

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@himgta @Verma Ashish Here's How I got D

Let L be a regular language- 0⁺1⁺

so L={01,001,0010...}

{xx| x ∈ L} according to me will be a CSL. Hence eliminated A and C.

For B and D I am not getting a proper example. Correct me if I am wrong.

 

 

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@Utkarsh Joshi

As per your approach!

Let L={a}

As it is finite ,it is regular 

{xx|x belongs to a}

means aa,this is also regular!

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himgta We have to look for a "counterexample" to eliminate some of the options!! we can come up with 100 such languages like you considered which conveys option A is correct. But it won't prove anything about class of a language. But even 1 counterexample is enough to prove/disprove something! I am trying to do that.

Answer 1

D is the ans