EXERCISE 5.3 Verify whether (a → b) → b is a tautology. Is the following proof correct? If not, what is wrong with it? 1: A, A → BE A → B AO 2: A, ABN A A0 3: A B B 4: (A → B) → B MP: 2,1 DT

EXERCISE 5.3 Verify whether (a → b) → b is a tautology. Is the following proof correct? If not, what is wrong with it? 1: A, A → BE A → B AO 2: A, ABN A A0 3: A B B 4: (A → B) → B MP: 2,1 DT

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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