2 votes 2 votes find regular expression over {a,b} corresponding to "set of strings containing at most 2a's." a) b*+ b*ab* + b*ab*ab* b) b*(a+ε)b*(a+ε) c) none Theory of Computation theory-of-computation regular-expression made-easy-booklet + – charul asked Oct 7, 2017 edited Mar 6, 2019 by ajaysoni1924 charul 839 views answer comment Share Follow See all 0 reply Please log in or register to add a comment.
2 votes 2 votes option B is correct. because language generated by option B is : a,aa,epsilon,ba,bba,baba,babba,bb......In any case atmost count of a is 2. with option A you can not get epsilon. sameerk answered Mar 29, 2019 sameerk comment Share Follow See all 0 reply Please log in or register to add a comment.
1 votes 1 votes possible string containing zero 'a'=ɛ +b*=b*. possible string containing one 'a'=b*ab*. possible string containing two 'a'=b*ab*ab*. so final answer is =b* + b*ab* + b*ab*ab*. option a is correct amit kumar 16 answered Oct 7, 2017 amit kumar 16 comment Share Follow See all 3 Comments See all 3 3 Comments reply charul commented Oct 7, 2017 reply Follow Share why not option b? 0 votes 0 votes amit kumar 16 commented Oct 7, 2017 reply Follow Share because string with two 'a' and end with two 'b' are not formed like b*ab*ab. 2 votes 2 votes Ram Swaroop commented Dec 19, 2018 reply Follow Share Nothing given about 2'b 0 votes 0 votes Please log in or register to add a comment.