Database System Concepts
7th Edition
ISBN: 9780078022159
Author: Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan
Publisher: McGraw-Hill Education
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Prove or disprove:
(a)∃ sets A,B ∀ functions f: A→B, f is a bijection.
(b) if f : A → B is a function, C ⊆ A, and D ⊆ B, then f : C → D is always a function.
[Note 1: one is true, the other is false.]
[Note 2: feel free to draw bubble-arrow pictures here, but make sure you explain what’s going on very carefully.]
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