English

Let R be the relation in the set {1, 2, 3, 4} given by R = {(1, 2), (2, 2), (1, 1), (4, 4), (1, 3), (3, 3), (3, 2)}. Choose the correct answer.

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Question

Let R be the relation in the set {1, 2, 3, 4} given by R = {(1, 2), (2, 2), (1, 1), (4, 4), (1, 3), (3, 3), (3, 2)}. Choose the correct answer.

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.

Explanation:

R is reflexive because (1, 1), (2, 2), (3, 3), (4, 4) ∈ R for all 1, 2, 3, 4 ∈ {1, 2, 3, 4}.

R is not symmetric because (1, 2) ∈ R but (2, 1) ∉ R for all 1, 2, ∈ {1, 2, 3, 4}.

R is transitive because (1, 3) ∈ R and (3, 2) ∈ R.

⇒ (1, 2) ∈ R for all 1, 2, 3 ∈ {1, 2, 3, 4}.

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Chapter 1: Relations and Functions - EXERCISE 1.1 [Page 7]

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NCERT Mathematics Part 1 and 2 [English] Class 12
Chapter 1 Relations and Functions
EXERCISE 1.1 | Q 15. | Page 7

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