English

If (1 + i)z = (1-i)z¯, then show that z = -iz¯.

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Question

If (1 + i)z = `(1 - i)barz`, then show that z = `-ibarz`.

Sum
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Solution

Given that: (1 + i)z = `(1 - i)barz`

⇒ `z/barz = (1 - i)/(1 + i)` = `(1 - i)/(1 + i) xx (1 - i)/(1 - i)`

= `(1 + i^2 - 2i)/(1 - i^2)` = `(1 - 1 - 2i)/(1 + 1)`

= `(-2i)/2` = –i

⇒ `z/barz` = –i

∴ z = `-i barz`

Hence proved.

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Chapter 5: Complex Numbers and Quadratic Equations - Exercise [Page 91]

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NCERT Exemplar Mathematics Exemplar [English] Class 11
Chapter 5 Complex Numbers and Quadratic Equations
Exercise | Q 7 | Page 91

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