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Evaluate: (1 + i)6 + (1 – i)3

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Question

Evaluate: (1 + i)6 + (1 – i)3 

Sum
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Solution

(1 + i)6 = {(1 + i)2}3

= (1 + i2 + 2i)3

= (1 – 1 + 2i)3

= 8i3

= –8i

And (1 – i)3 = 1 – i3 – 3i + 3i2

= 1 + i – 3i – 3

= –2 – 2i

Therefore, (1 + i)6 + (1 – i)3

= –8i – 2 – 2i

= –2 – 10i

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Chapter 5: Complex Numbers and Quadratic Equations - Solved Examples [Page 78]

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NCERT Exemplar Mathematics [English] Class 11
Chapter 5 Complex Numbers and Quadratic Equations
Solved Examples | Q 1 | Page 78

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