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If a + ib = (x+i)22x2+1 prove that a2 + b2 = (x2+1)2(2x+1)2

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Question

If a + ib  = `(x + i)^2/(2x^2 + 1)` prove that a2 + b= `(x^2 + 1)^2/(2x + 1)^2`

Sum
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Solution

`a + ib  = (x + i)^2/(2x^2 + 1)  ......(1)` 

i के स्थान पर – i रखने से

By replacing i with –i

`a - ib  = (x + i)^2/(2x^2 + 1)  ......(2)` 

समी. (1) और (2) का गुणा करने पर

On multiplying equations (1) and (2)

`(a + ib)(a - ib)  = (x + i)^2/(2x^2 + 1) xx (x - i)^2/(2x^2 + 1)`

or `a^2  -  i^2b^2  =  [(x+i)(x - i)]^2/(2x^2  + 1)^2`

or `a^2 + b^2  = (x^2 - i^2)^2/(2x^2 + 1)^2`

or `a^2 + b^2  = (x^2  + 1)^2/(2x^2 + 1)^2`

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Chapter 4: Complex Numbers and Quadratic Equations - Miscellaneous Exercise [Page 86]

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NCERT Mathematics [English] Class 11
Chapter 4 Complex Numbers and Quadratic Equations
Miscellaneous Exercise | Q 6. | Page 86

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