Question

What is the number of states in the minimal DFA with input symbols {0,1,2} where 2nd last symbol is 1?

A. 8

B. 9

C. 6

D. None

Comments

can somebody please explain the answer diagramatically..

Answer 1

Second last symbol is 1 over {0,1, 2 }

regular expression = (0+1+2)*1(0+1+2).                     Anything Second last Last

For this regular expression NFA is

Convert NFA to DFA

Comments

In such questions where the number of states in minimal DFA is asked, do we have to count the trap state also?

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Yes, for sure in DFA

Answer 2

D. None of these

Comments

What is the number of states?

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Coming as 4

Answer 3

B. 
Whenever the question says the nth symbol from the right side is fixed and the input language has m symbols the answer for minimal dfa is mⁿ  . So 3² = 9

Comments

Please can you explain how this formula came?

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but here according to your formula answer coming out to be  8 but answer is 4 how