Q. 73.7( 3 Votes )

# Mark the correct alternative in the following:

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.

Answer :

We have *x*φ*y* |*x*| = *y*

By checking the options,

A. (2 + 3*i*) φ 13

X = 2 + 3i;

= √13

Therefore, |x|≠ y.

So, option A is incorrect.

B. 3 φ (−3)

X = 3;

= 3

3 ≠(-3)

Therefore, option B is incorrect.

C. (1 + *i*) φ 2

X = 1+ i;

= √2

√2 ≠ 2

Therefore, option C is also incorrect.

D. *i*φ 1

x = i;

= 1

1 = 1

|x| = y.

Therefore, option D is correct.

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