Question: a. Let C be a context-free language and R be a regular language. Prove that the language C R is context free. b. Let

a. Let C be a context-free language and R be a regular language. Prove that the language C \ R is context free.

b. Let A = {w|w ∈ {a, b, c}* and w contains equal numbers of a’s, b’s, and c’s}. Use part (a) to show that A is not a CFL.

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