Let A = {1,5,8,9). Are the following relations on A reflexive? 1. {(9,8), (8, 1), (1, 5), (9, 9), (8, 8)} 2. {(8,5), (9, 9), (5, 1), (1, 1)} 3. {(9, 1), (5,9), (9, 9), (8, 8), (1, 1)} ? ? ? V V 13 ? ? 4. {(9,5), (1,9), (5,8), (8, 8), (1, 1)} ✓ 5. {(9, 9), (8, 8), (1, 1), (5, 5), (9, 5), (5, 1)} 6. {(9,9), (8, 8), (1, 1), (5, 5), (8,5)}

Let A = {1,5,8,9). Are the following relations on A reflexive? 1. {(9,8), (8, 1), (1, 5), (9, 9), (8, 8)} 2. {(8,5), (9, 9), (5, 1), (1, 1)} 3. {(9, 1), (5,9), (9, 9), (8, 8), (1, 1)} ? ? ? V V 13 ? ? 4. {(9,5), (1,9), (5,8), (8, 8), (1, 1)} ✓ 5. {(9, 9), (8, 8), (1, 1), (5, 5), (9, 5), (5, 1)} 6. {(9,9), (8, 8), (1, 1), (5, 5), (8,5)}

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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