Question

Whcih of the following problems is decidable?
a. whether a turing machine has at least three states
b. whether a turing machine will ever halt
c. whether a turing machine will ever print a symbol
d. whether a turing machine will ever enter a designated state

Answer 1

Answer on Question#38655 - <math> - <other>.

Whcih of the following problems is decidable?

a. whether a turing machine has at least three states

b. whether a turing machine will ever halt

c. whether a turing machine will ever print a symbol

d. whether a turing machine will ever enter a designated state

Solution. a) This problem can be decidable, but there are insufficient conditions.

b) If a turing machine has been halted, it means that problem is decidable

c,d) If a turing machine will ever print a symbol or enter a designated state, then it never halts.

Answer: b) whether a turing machine will ever halt