We learnt in class/Notes that A[x] → (Vx)A[x] is NOT atheorem if x indeed occurs free in A.Yet, I think I got a proof: First, let me use DThm and prove insteadA[a] F (Væ)A[a]:1) A[a]2) (Væ)A[x] (1 + Gen)(hуp)Something must be wrong in my "PROOF"! What EXACTLY (not toomany words please and above all don't say "it's not a theorem"!)2.

2. We learnt in class/Notes that A[x] → (Vx)A[x] is NOT a theorem if x indeed occurs free in A. Yet, I think I got a proof: First, let me use DThm and prove instead A[a] F (Væ)A[x]: A[a] 1) 2) (Væ)A[x] (1+ Gen) (hyp) Something must be wrong in my “PROOF"! What EXACTLY (not too many words please and above all don't say "it's not a theorem"!)

2. We learnt in class/Notes that A[x] → (Vx)A[x] is NOT a theorem if x indeed occurs free in A. Yet, I think I got a proof: First, let me use DThm and prove instead A[a] F (Væ)A[x]: A[a] 1) 2) (Væ)A[x] (1+ Gen) (hyp) Something must be wrong in my “PROOF"! What EXACTLY (not too many words please and above all don't say "it's not a theorem"!)

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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