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Given the Relation R = {(1, 2), (2, 3)} on the Set a = {1, 2, 3}, Add a Minimum Number of Ordered Pairs So that the Enlarged Relation is Symmeteric, Transitive and Reflexive.

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Question

Given the relation R = {(1, 2), (2, 3)} on the set A = {1, 2, 3}, add a minimum number of ordered pairs so that the enlarged relation is symmeteric, transitive and reflexive.

Sum
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Solution

We have,

R = {(1, 2), (2, 3)}

R can be a transitive only when the elements (1, 3) is added

R can be a reflexive only when the elements (1, 1), (2, 2), (3, 3) are added

R can be a symmetric only when the elements (2, 1), (3, 1) and (3, 2) are added

So, the required enlarged relation, R' = {(1, 1), (1, 2), (1, 3), (2, 1), (2, 2), (2, 3), (3, 1), (3, 2), (3, 3)} =  A × A

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Chapter 1: Relations - Exercise 1.1 [Page 11]

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R.D. Sharma Mathematics Volume 1 and 2 [English] Class 12
Chapter 1 Relations
Exercise 1.1 | Q 15 | Page 11

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