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Given an example of a relation. Which is reflexive and symmetric but not transitive.

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Question

Given an example of a relation. Which is reflexive and symmetric but not transitive.

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Solution

Let A = {4, 6, 8}.

Define a relation R on A as:

A = {(4, 4), (6, 6), (8, 8), (4, 6), (6, 4), (6, 8), (8, 6)}

Relation R is reflexive since for every a ∈ A, (a, a) ∈ R i.e., (4, 4), (6, 6), (8, 8)} ∈ R.

Relation R is symmetric since (a, b) ∈ R ⇒ (b, a) ∈ R for all a, b ∈ R.

Relation R is not transitive since (4, 6), (6, 8) ∈ R, but (4, 8) ∉ R.

Hence, relation R is reflexive and symmetric but not transitive.

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Chapter 1: Relations and Functions - EXERCISE 1.1 [Page 6]

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NCERT Mathematics Part 1 and 2 [English] Class 12
Chapter 1 Relations and Functions
EXERCISE 1.1 | Q 10. (iii) | Page 6

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