English

The maximum number of equivalence relations on the set A = {1, 2, 3} are ______.

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Question

The maximum number of equivalence relations on the set A = {1, 2, 3} are ______.

Options

  • 1

  • 2

  • 3

  • 5

MCQ
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Solution

The maximum number of equivalence relations on the set A = {1, 2, 3} are 5.

Explanation:

Given, set A = {1, 2, 3}

Now, the number of equivalence relations as follows

R1 = {(1, 1), (2, 2), (3, 3)}

R2 = {(1, 1), (2, 2), (3, 3), (1, 2), (2, 1)}

R3 = {(1, 1), (2, 2), (3, 3), (1, 3), (3, 1)}

R4 = {(1, 1), (2, 2), (3, 3), (2, 3), (3, 2)}

R5 = {(1, 2, 3) ⇔ A x A = A2}

Thus, maximum number of equivalence relation is ‘5’.

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Chapter 1: Relations And Functions - Exercise [Page 14]

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NCERT Exemplar Mathematics [English] Class 12
Chapter 1 Relations And Functions
Exercise | Q 30 | Page 14

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