3 votes 3 votes If L1 = Regular L and L2 = CFL then L1 UNION L2? = L1 U L2 = Reg L U CFL = CFL U CFL = CFL is it True? Theory of Computation theory-of-computation closure-property regular-language context-free-language + – iarnav asked Nov 1, 2017 iarnav 556 views answer comment Share Follow See all 2 Comments See all 2 2 Comments reply Manu Thakur commented Nov 1, 2017 i edited Nov 1, 2017 reply Follow Share yes correct! but this approach will fail for DCFL as DCFL is not closed under UNION. by the way, every language is closed under regular union and regular intersection. 0 votes 0 votes iarnav commented Nov 1, 2017 reply Follow Share Thank you! 0 votes 0 votes Please log in or register to add a comment.
2 votes 2 votes Yes you are right L1= w L2= wxw L1 u L2 ={w,wxw} which is cfl not regular sonveer tomar 1 answered Nov 5, 2017 sonveer tomar 1 comment Share Follow See all 0 reply Please log in or register to add a comment.