Beginner
Theory of Computation
Q32 / 100
What is a language that is RE but not decidable?
Correct! Well done.
Incorrect.
The correct answer is B) The Halting Problem language {<M,w> | M halts on w}
B
Correct Answer
The Halting Problem language {<M,w> | M halts on w}
Explanation
The Halting Problem is RE (a TM can accept by simulating M on w until it halts) but undecidable (no TM always halts on both instances). Its complement is not even RE.
Progress
32/100