English

Let R be a relation on the set N of natural numbers defined by nRm if n divides m. Then R is ______.

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Question

Let R be a relation on the set N of natural numbers defined by nRm if n divides m. Then R is ______.

Options

  • Reflexive and symmetric

  • Transitive and symmetric

  • Equivalence

  • Reflexive, transitive but not symmetric

MCQ
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Solution

Let R be a relation on the set N of natural numbers defined by nRm if n divides m. Then R is reflexive, transitive but not symmetric.

Explanation:

Since n divides n, ∀ n ∈ N, R is reflexive.

R is not symmetric since for 3, 6 ∈ N, 3 R 6 ≠ 6 R 3.

R is transitive since for n, m, r whenever n/m and m/r ⇒ n/r,

i.e., n divides m and m divides r, then n will devide r.

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Chapter 1: Relations And Functions - Solved Examples [Page 8]

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NCERT Exemplar Mathematics Exemplar [English] Class 12
Chapter 1 Relations And Functions
Solved Examples | Q 17 | Page 8

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