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If A = {1, 2, 3, 4 }, define relations on A which have properties of being: reflexive, symmetric and transitive

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Question

If A = {1, 2, 3, 4 }, define relations on A which have properties of being: 
reflexive, symmetric and transitive

Sum
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Solution

Given that, A = {1, 2, 3}.

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

R3 is reflexive as (1, 1) (2, 2) and (3, 3) ∈ R1

R3 is symmetric as (1, 2), (1, 3), (2, 3) ∈ R1 ⇒ (2, 1), (3, 1), (3, 2) ∈ R1

Therefore, Ris reflexive, symmetric and transitive.

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Chapter 1: Relations And Functions - Exercise [Page 12]

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NCERT Exemplar Mathematics Exemplar [English] Class 12
Chapter 1 Relations And Functions
Exercise | Q 16. (c) | Page 12

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