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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 + 3i) ϕ 13 (B) 3ϕ (−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

  • (a) (2 + 3i) ϕ 13

  • (b) 3ϕ (−3)

  • (c) (1 + i) ϕ 2

  • (d) i ϕ 1

     
MCQ
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Solution

(d) i ϕ 1

We have \[\left| i \right| = \sqrt{1^2 + 0^2} = 1\]

Thus, i ϕ 1 satisfies x ϕ y ⇔
|x| = y .
 
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Chapter 2: Relations - Exercise 2.5 [Page 26]

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R.D. Sharma Mathematics [English] Class 11
Chapter 2 Relations
Exercise 2.5 | Q 7 | Page 26

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