GATE | GATE-CS-2015 (Set 2) | Question 65
Consider the following statements:
1. The complement of every Turning decidable language is Turning decidable 2. There exists some language which is in NP but is not Turing decidable 3. If L is a language in NP, L is Turing decidable
Which of the above statements is/are True?
(A) Only 2
(B) Only 3
(C) Only 1 and 2
(D) Only 1 and 3
1 is true: Complement of Turing decidable is Turing Decidable. 3 is true. All NP problems are Turing decidable (See https://www.geeksforgeeks.org/np-completeness-set-1/) 2 is false: The definition of NP itself says solvable in polynomial time using non-deterministic Turing machine.
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