(10) Let L = { <M> | M is a TM that accepts sR whenever it accepts s } . Show that L is undecidable.
Let Show that L is undecidable L = {〈M) IM is a Turing Machine that accepts w whenever it accepts L = {〈M) IM is a Turing Machine that accepts w whenever it accepts
Let REPEATTM = { | M is a TM, and for all s L(M), s = uv where u = v }. Show that REPEATTM is undecidable. Do not use Rice’s Theorem. Let REPEATTM = { <M>M is a TM, and for all s E L(M), s = uv where u = v}. Show that REPEATM is undecidable. Do not use Rice's Theorem.
8. (15) Let REPEATTM = { <M>M is a TM, and for all s € L(M), s = uv where u = v}. Show that REPEATM is undecidable. Do not use Rice's Theorem.
Let REPEATTM = {<M> Mis a TM, and for all s E L(M), s = uv where u =v}. Show that REPEATTM is undecidable. Do not use Rice's Theorem.
8. (15) Let REPEATTM = { <M> | M is a TM, and for all s L(M), s = uv where u = v }. Show that REPEATTM is undecidable. Do not use Rice’s Theorem. 7. (15) PALINDROIVIDACI vy provimo ETUS in polynomial time. 8. (15) Let REPEATTM = { <M>M is a TM, and for all s € L(M), s = uv where u =v}. Show that REPEATTM is undecidable. Do not use Rice's Theorem. ai
3. Let T = {< M > | m accepts w" when it accepts w. }. Show T is undecidable.
19. (1 point) Suppose that L is undecidable and L is recognizable. Which of the following could be false? A. I is co-Turing recognizable. B. I is not recognizable. C. I is undecidable. D. L* is not recognizable. E. None of the above. 20. (2 points) Let ETM {(M)|L(M) = 0} and EQTM = {(M1, M2)|L(Mi) = L(M2)}. We want to show that EQTM is undecidable by reducing Etm to EQTM and we do this by assuming R is a...
Show that FINITETM = {<M> : M is a TM and L(M) is finite} is undecidable.
2. Let L-M M): M is a Turing machine that accepts at least two binary strings. a) Define the notions of a recognisable language and an undecidable language. [5 marks [5 marks] b) Is L Turing-recognisable? Justify your answer with an informal argument. c) Prove that L is undecidable. (Hint: use Rice's theorem.) [20 marks] 20 marks] d) Bonus: Justify with a formal proof your answer to b). 2. Let L-M M): M is a Turing machine that accepts at...
2. Let L = {hMi: M is a Turing machine that accepts at least two binary strings}. a) Define the notions of a recognisable language and an undecidable language. [5 marks] b) Is L Turing-recognisable? Justify your answer with an informal argument. [5 marks] c) Prove that L is undecidable. (Hint: use Rice’s theorem.) [20 marks] d) Bonus: Justify with a formal proof your answer to b). [20 marks] 2. Let L-M M): M is a Turing machine that accepts...