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Question

Define languages L0 and L1 as follows :

L0 = {< M, w, 0 > | M halts on w}
L1 = {< M, w, 1 > | M does not halts on w}

Here < M, w, i > is a triplet, whose first component. M is an encoding of a Turing Machine, second component, w, is a string, and third component, i, is a bit. Let L = L0 ∪ L1. Which of the following is true ?

a.

L is recursively enumerable, but L' is not

b.

L' is recursively enumerable, but L is not

c.

Both L and L' are recursive

d.

Neither L nor L' is recursively enumerable

Answer: (a).L is recursively enumerable, but L' is not

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Q. Define languages L0 and L1 as follows : L0 = {< M, w, 0 > | M halts on w} L1 = {< M, w, 1 > | M does not halts on w} Here < M, w, i > is a triplet, whose first component. M...

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