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Given an Example of a Relation. Which Is Symmetric and Transitive but Not Reflexive. - Mathematics

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Question

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

Solution

Let A = {−5, −6}.

Define a relation R on A as:

R = {(−5, −6), (−6, −5), (−5, −5)}

Relation R is not reflexive as (−6, −6) ∉ R.

Relation R is symmetric as (−5, −6) ∈ R and (−6, −5}∈R.

It is seen that (−5, −6), (−6, −5) ∈ R. Also, (−5, −5) ∈ R.

∴The relation R is transitive.

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

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

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NCERT Mathematics [English] Class 12
Chapter 1 Relations and Functions
Exercise 1.1 | Q 10.5 | Page 6

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