## Discussion Forum

Que. | The symmetric difference of two sets S1 and S2 is defined as
S1ΘS2 = {x|xϵS1 or xϵS2, but x is not in both S1 and S2} The nor of two languages is defined as nor (L1,L2) = {w|w ∉ L1 and w|w ∉ L2} Which of the following is correct? |

a. | The family of regular languages is closed under symmetric difference but not closed under nor |

b. | The family of regular languages is closed under nor but not closed under symmetric difference |

c. | The family of regular languages are closed under both symmetric difference and nor |

d. | The family of regular languages are not closed under both symmetric difference and nor |

Answer:The family of regular languages are closed under both symmetric difference and nor |