2006b question 2
The answer is c.
Answer c states that for DFA A with "a" states and DFA B with b states, there doesn't exist a DFA which accepts A union B and has O(a+b) states.
Consider this example which contradicts answer c:
A and B accepts the same language, so there definitely exists a DFA with O(a+b) states, specifically min(a,b) states.
Could you please clarify why this does not contradict answer c.
2007a question 9
The answer is e.
Could you please clarify why answer c is incorrect, it seems that the pumping lemma application described in the answer is correct. Maybe except for the "for all n" part where it should be a pumping constant
Thanks in advanced.