0 votes 0 votes Find the regular expression No 2 a's and 2 b's should come together? Theory of Computation theory-of-computation + – gabbar asked Feb 19, 2017 gabbar 3.6k views answer comment Share Follow See all 10 Comments See all 10 10 Comments reply Show 7 previous comments gabbar commented Feb 19, 2017 reply Follow Share Thnq for ur suggestion.:) . Really nptel course are so boring I have watched her video.but.for toc its better to watch shai simonson video rather than nptel.. :) 0 votes 0 votes Vivek Jain commented Feb 19, 2017 reply Follow Share it means select epsilon or b from the first part From the second part u can get any number of ab And from the third part u can select a or epsilon. 0 votes 0 votes Devshree Dubey commented Feb 19, 2017 reply Follow Share No probs. Work out d way u feel it's better. Yeah. :) 0 votes 0 votes Please log in or register to add a comment.
1 votes 1 votes No two a's and b's should come together..so language is L=(Epsilon+b)(ab)* (a+Epsilon). L={Epsilon, b, a, ab,abab,....,bab,babab,....aba,ababa,....} Vivek Jain answered Feb 19, 2017 Vivek Jain comment Share Follow See all 0 reply Please log in or register to add a comment.
0 votes 0 votes (a+€) (ba) * (b+€) + a+b+ab+€ Explanation : The only possible strings is a followed by b and b followed by a tht is bababa..... So we get (ba) * But strings could also start with a and could also end with b So we add (€+a) and (b+€) at the start and the end But the minimum possible string in our regular expression is ba which means we have left some strings So we add ab+a+b+€ in the end to cover all possible strings bhargav9873 answered Feb 26, 2017 bhargav9873 comment Share Follow See all 0 reply Please log in or register to add a comment.
0 votes 0 votes alphabets= { a , b } L={ epsilon , a , b , ab , ba , aba , bab , abab ,...........................} it's infinite language It may have these two answers 1) (epsilon+b)(ab)*(epsilon+a) or 2) (epsilon+a)(ba)*(epsilon+b) Both of them are correct shivam001 answered May 20, 2019 shivam001 comment Share Follow See all 0 reply Please log in or register to add a comment.
0 votes 0 votes RE : (a+ba)(ba)* + (b+ab)(ab)* + ϵ tech_beardo answered Nov 25, 2019 tech_beardo comment Share Follow See all 0 reply Please log in or register to add a comment.