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+13 votes

02. Choose the correct alternatives (more than one may be correct) and write the corresponding letters only:

(xix) Context-free languages are

  1. closed under union
  2. closed under complementation
  3. closed under intersection
  4. closed under Kleene closure


asked in Theory of Computation by Veteran (68.8k points)
retagged by | 387 views

2 Answers

+13 votes
Best answer
Answer: A, D

Context Free languages are not closed under intersection and complementation.
answered by Veteran (35.8k points)
selected by
CFG are closed under Union , Kleen closure & Concatenation .

Also CFG are closed under Regular intersection

BUT , are CFG closed under Regular Union ?

I think yes...coz..every regular is CFG & CFG are closed under union ....

correct me if I am wrong
+1 vote


According to the above table we can say , A and D is correct answer



answered by Loyal (3.3k points)
wat is GSM mapping ??

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