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Let A = {1, 2, 3} and consider the relation R = {1, 1), (2, 2), (3, 3), (1, 2), (2, 3), (1,3)}. Then R is ______. - Mathematics

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Question

Let A = {1, 2, 3} and consider the relation R = {1, 1), (2, 2), (3, 3), (1, 2), (2, 3), (1,3)}. Then R is ______.

Options

  • Reflexive but not symmetric

  • Reflexive but not transitive

  • Symmetric and transitive

  • Neither symmetric, nor transitive

MCQ
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Solution

Let A = {1, 2, 3} and consider the relation R = {1, 1), (2, 2), (3, 3), (1, 2), (2, 3), (1,3)}. Then R is reflexive but not symmetric.

Explanation:

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

R = {(1, 1), (2, 2), (3, 3), (1, 2), (2, 3),(1, 3)}

∵ (1, 1), (2, 2),(3, 3) ∈ R

Hence, R is reflexive.

(1, 2) ∈ R but (2, 1) ∉ R

Hence, R is not symmetric.

(1, 2) ∈ R and (2, 3) ∈ R

⇒ (1, 3) ∈ R

Hence, R is transtive.

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Chapter 1: Relations And Functions - Exercise [Page 14]

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NCERT Exemplar Mathematics [English] Class 12
Chapter 1 Relations And Functions
Exercise | Q 33 | Page 14

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