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let L be a recursive enumerable language then which of the following is true

(a) complement of L is decidable or undecidable but not semi decidable.

(b)complement of L is undecidable.

(c)complement of L is either decidable or semi decidable

(d) complement of L is undecidable but partially decidable.

I am confused with meaning of semi decidable and partially decidable
asked in Theory of Computation by Junior (795 points) | 15 views
I think both are same..
what will be the answer.???explain
Complement of RE can be RE(which means REC too) or not RE.

if it is RE, then it is decidable, if it is not RE then it is undecidable.

So we can say that it is either decidable or undecidable but not partially decidable.

(RE is partially decidable)

But those languages which are RE but not REC, their complement is undecidable.

Here nothing is given,that's why I assumed that given RE may or may not be REC too.

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