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Let R Be the Relation on the Set A = {1, 2, 3, 4} Given by R = {(1, 2), (2, 2), (1, 1), (4, 4), (1, 3), (3, 3), (3, 2)}. Then, (A) R Is Reflexive and Symmetric but Not Transitive (B) R Is

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Question

Let R be the relation on the set A = {1, 2, 3, 4} given by R = {(1, 2), (2, 2), (1, 1), (4, 4), (1, 3), (3, 3), (3, 2)}. Then, _____________________ .

Options

  • R is reflexive and symmetric but not transitive

  • R is reflexive and transitive but not symmetric

  • R is symmetric and transitive but not reflexive

  • R is an equivalence relation

MCQ
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Solution

R is reflexive and transitive but not symmetric.

Reflexivity: Clearly, (a, a∈ R  A

So, R is reflexive on A.

Symmetry :  Since (1, 2∈ R, but (2, 1∉ R,

R is not symmetric on A.

Transitivity : Since, (1, 3), (3, 2∈ R and (1, 2∈ R,

R is transitive on A.

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Chapter 1: Relations - Exercise 1.4 [Page 32]

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R.D. Sharma Mathematics Volume 1 and 2 [English] Class 12
Chapter 1 Relations
Exercise 1.4 | Q 22 | Page 32

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