English

Let a = {2, 3, 4, 5, ..., 17, 18}. Let '≃' Be the Equivalence Relation on a × A, Cartesian Product of a with Itself, Defined by (A, B) ≃ (C, D) If Ad = Bc. Then, the Number of Ordered Pairs of the

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Question

Let A = {2, 3, 4, 5, ..., 17, 18}. Let '≃' be the equivalence relation on A × A, cartesian product of Awith itself, defined by (a, b) ≃ (c, d) if ad = bc. Then, the number of ordered pairs of the equivalence class of (3, 2) is _______________ .

Options

  • 4

  • 5

  • 6

  • 7

MCQ
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Solution

6
The ordered pairs of the equivalence class of (3, 2) are {(3, 2), (6, 4), (9, 6), (12, 8), (15, 10), (18, 12)}.
We observe that these are 6 pairs.

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Chapter 1: Relations - Exercise 1.4 [Page 31]

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R.D. Sharma Mathematics Volume 1 and 2 [English] Class 12
Chapter 1 Relations
Exercise 1.4 | Q 7 | Page 31

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