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Question
Prove the following properties:
z is real if and only if z = `bar(z)`
Solution
z is real if z = `bar(z)`
Let z = x + iy
z = `bar(z)`
⇒ x + iy = x – iy
⇒ 2iy = 0
⇒ y = 0
⇒ z is real.
Z is real if z = `bar(z)`
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