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In: Computer Science

Prove the following Closure Properties with respect to Context Free Languages. 1. Show that Context Free...

Prove the following Closure Properties with respect to Context Free Languages.

1. Show that Context Free Languages are Closed under union(∪), concatenation(·), kleene star(*).

(Hint: If L1 and L2 are Context Free languages then write Context Free grammar equivalent to L1 ∪ L2, L1 · L2, L∗ 1 )

2. Show that if L1 and L2 are Context Free Languages, then L1 ∩ L2 is not necessarily Context Free.

(Hint: Use Proof by Counter Example)

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