GATE CS 2022 Set 1 — Question 12
Go beyond PYQs with Success TrackerAI-powered personalised practice and doubt support. Unlimited practice on eligible plans; AI usage limits apply.MCQ+1 / -0.33MediumRegular ExpressionsFinite Automata & Regular LanguagesTheory of ComputationDFA to RE
Theory of Computation → Finite Automata & Regular Languages → DFA to RE
Last updated
Question
Which one of the following regular expressions correctly represents the language of the finite automaton given below?
Correct answer
(D) (ba^ a + ab^ b)^ (ab^ + ba^)
Solution
The finite automaton (NFA) has the following structure:
Finally, to accept, it must transition to (path ) or (path ).Combining these, the regular expression is: .
- Start state .
- Transition (where is an accepting state).
- Transition (where is an accepting state).
- From : Self-loop , and transition back to . This creates a loop , represented by .
- From : Self-loop , and transition back to . This creates a loop , represented by .
Finally, to accept, it must transition to (path ) or (path ).Combining these, the regular expression is: .
Continue learning with Success Tracker
A step still unclear? Work through it with support
Use Success Tracker to ask about the reasoning, then try another GATE CS question to check your understanding.
AI-powered practice· Unlimited practice on eligible plans
- PYQs with solutions
- Attempt available previous-year questions, then compare your reasoning with the worked solution. Coverage varies by stream.
- Practice that adapts
- Choose a topic, work on weaker areas and bookmark questions to revisit. Your attempts feed your progress tracking.
- AI doubt support
- Ask follow-up questions about a step or concept while practising, instead of stopping at the final answer.
Unlimited practice is available on eligible plans. Free practice and AI usage have limits; check the current plan allowances before choosing.
This page stays readable without an account. AI responses can be wrong; check them against the solution and source material.
More questions on Finite Automata & Regular Languages
2026 Set 2 Q13Which one of the following statements is equivalent to the following assertion? Turing machine …2026 Set 1 Q25Consider the following grammar where is the start symbol, and and are terminal symbols.…2026 Set 1 Q26Let be a nondeterministic finite automaton (NFA) with 6 states over a finite alphabet. Which of…2026 Set 2 Q29Which of the following grammars is/are ambiguous?2026 Set 2 Q47Consider the following two finite automata and . [figure] Which of the following…