Let A={a.b.c.de) and S, T, U and V relations on A whereS= {(a.a), (ab), (bea), (bd), (Ge), (ed), (aa)}T= {(ab), (ka), (ks), (kd), lee), (de), (ab)}U= {(a,b), (aa), (bc), (bub), (ee), (ba), (ab), (ac), (d.d), lac), (ea}V= {(ab), (kc), (kb), lee), (ka), (ab), (dd), las), (a)}a) Which of the relations are reflexive? Justify your answer.b) Which of the relations are antisymmetric? Justify your answer.c) Find Un V.d) Find T-S.

Let A={g.b.c.d.e} and S, T, U and V relations on A where S = {(aa), (ab), (bc), (kd), (ce), (ed), (aa)} T= {(g,b), (ka), (ks), (kd), lee), (de), (ab)} U= {(a,b), (a,a), (b.c), (k.b), (ee), (ka), (ab), (ac), (dd), (ac), (cl} V= {(gb), (k), (kb), lee), ka), (sb), (dd), los), leal} a) Which of the relations are reflexive? Justify your answer. b) Which of the relations are antisymmetric? Justify your answer. c) Find Un V. d) Find T-S.

Let A={g.b.c.d.e} and S, T, U and V relations on A where S = {(aa), (ab), (bc), (kd), (ce), (ed), (aa)} T= {(g,b), (ka), (ks), (kd), lee), (de), (ab)} U= {(a,b), (a,a), (b.c), (k.b), (ee), (ka), (ab), (ac), (dd), (ac), (cl} V= {(gb), (k), (kb), lee), ka), (sb), (dd), los), leal} a) Which of the relations are reflexive? Justify your answer. b) Which of the relations are antisymmetric? Justify your answer. c) Find Un V. d) Find T-S.

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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