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A Relation ϕ from C to R is Defined by X ϕ Y ⇔ | X | = Y. Which One is Correct? (A) (2 + 3 I) ϕ 13 (B) 3 ϕ (−3) (C) (1 + I) ϕ 2 (D) I ϕ 1

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Question

A relation ϕ from C to R is defined by x ϕ y ⇔ | x | = y. Which one is correct?

Options

  • (2 + 3 i) ϕ 13

  • 3 ϕ (−3)

  • (1 + i) ϕ 2

  • i ϕ 1

MCQ
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Solution

i ϕ 1

∵ `| 2 +3 | = sqrt13 ≠ 13`

|3| ≠ -3

 `| 1+ i| = sqrt2 ≠2`

and | i |=1

So, (i, 1) ∈ ϕ

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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 12 | Page 32

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