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Let R be the relation in the set N given by R = {(a, b): a = b − 2, b > 6}. Choose the correct answer. - Mathematics

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Question

Let R be the relation in the set given by R = {(a, b): a = b − 2, b > 6}. Choose the correct answer.

Options

  • (2, 4) ∈ R

  • (3, 8) ∈ R

  • (6, 8) ∈ R

  • (8, 7) ∈ R

MCQ

Solution

(6, 8) ∈ R

Explanation:

R = {(a, b): a = b - 2, b > 6}

Here, since b > 6, hence (2, 4) ∉ R and

3 ≠ 8 – 2, ∴ (3, 8) ∉ R and

8 ≠ 7 – 2, ∴ (8, 7) ∉ R

Now for (6, 8), 8 > 6 and 6 = 8 – 2

∴ (6, 8) ∈ R ≠ R

Hence, option (6, 8) ∈ R is correct.

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

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NCERT Mathematics [English] Class 12
Chapter 1 Relations and Functions
Exercise 1.1 | Q 16 | Page 7

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