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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
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Solution
(d) i ϕ 1
We have \[\left| i \right| = \sqrt{1^2 + 0^2} = 1\]
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