The correct statements are: If L₁ and L₂ are not regular languages, then L₁ U L₂ cannot be regular. If L₁ and L₂ are regular languages, then L₁ L₂ = {w: w€ (L₁-L₂) or w€ (L₂ - L₁)} is regular. It is possible that the union of a regular language and a nonregular language is regular. Every subset of a regular language is regular.

The correct statements are: If L₁ and L₂ are not regular languages, then L₁ U L₂ cannot be regular. If L₁ and L₂ are regular languages, then L₁ L₂ = {w: w€ (L₁-L₂) or w€ (L₂ - L₁)} is regular. It is possible that the union of a regular language and a nonregular language is regular. Every subset of a regular language is regular.

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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