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Which one of the following languages over Σ = {𝑎, 𝑏} is NOT context-free?

Q. Which one of the following languages over Σ = {𝑎, 𝑏} is NOT context-free?

(A) {𝑤𝑤^𝑅 |𝑤 ∈ {𝑎, 𝑏}^∗}

(B) {𝑤𝑎^𝑛𝑏^𝑛𝑤^𝑅 |𝑤 ∈ {𝑎, 𝑏}^∗, 𝑛 ≥ 0}

(C) {𝑤𝑎^𝑛𝑤^𝑅𝑏^𝑛 |𝑤 ∈ {𝑎, 𝑏}^∗, 𝑛 ≥ 0}

(D) {𝑎^𝑛𝑏^𝑖 | 𝑖 ∈ {𝑛, 3𝑛, 5𝑛}, 𝑛 ≥ 0}

Ans: {waⁿw^Rbⁿ ⏐ w ∈ {a, b}*, n≥ 0}

Next Read: Let the set of functional dependencies F = {QR → S, R → P, S → Q} hold on a relation schema X = (PQRS). X is not in BCNF. Suppose X is decomposed into two schemas Y and Z »

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