0 votes 0 votes Is set difference operation is closed for two CFLs say L1 and L2? Please justify your answer. Theory of Computation theory-of-computation + – S Ram asked Dec 4, 2018 S Ram 213 views answer comment Share Follow See all 3 Comments See all 3 3 Comments reply Prateek Raghuvanshi commented Dec 4, 2018 reply Follow Share set difference means $L_1-L_2$ =$L_1\cap \sim L_2$ as we know CFL is not closed under complement so we can say about set difference of CFL's is not closed. 0 votes 0 votes S Ram commented Dec 4, 2018 reply Follow Share Then how the aswer is only B here? Can u please justify the significance of "not necessarily" here ? https://gateoverflow.in/2737/gate1996-2-8 0 votes 0 votes Prateek Raghuvanshi commented Dec 4, 2018 reply Follow Share CFL'S are not closed under intersection,so intersection of two CFL may or may not be cfl. 0 votes 0 votes Please log in or register to add a comment.