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If A = {1, 2, 3, 4 }, define relations on A which have properties of being: reflexive, transitive but not symmetric

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Question

If A = {1, 2, 3, 4 }, define relations on A which have properties of being:
reflexive, transitive but not symmetric

Sum
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Solution

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

Let R1 = {(1, 1), (1, 2), (1, 3), (2, 3), (2, 2), (1, 3), (3, 3)}

R1 is reflexive as (1, 1), (2, 2) and (3, 3) lie is R1.

R1 is transitive as (1, 2) ∈ R1, (2, 3) ∈ R1 ⇒ (1, 3) ∈ R1

Now, (1, 2) ∈ R1 ⇒ (2, 1) ∉ R1.

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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. (a) | Page 12

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