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Express the given complex number in the form a + ib: (13+3i)3

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Question

Express the given complex number in the form a + ib: `(1/3 + 3i)^3`

Sum
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Solution

`(1/3 + 3i)^3 = (1/3)^3 + 3 (1/3)^2 (3i) + 3(1/3) (3i)^2 + (3i)^3`

= `1/27 + 27i^3 + 9i^2`

= `1/27 + 27 (-i) + i + 9 (-1)`

= `1/27 - 9 + i (1 - 27)`

= `(1 - 243)/27 + i (-26)`

= `(- 242)/27 - 26i`

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Chapter 4: Complex Numbers and Quadratic Equations - EXERCISE 4.1 [Page 83]

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NCERT Mathematics [English] Class 11
Chapter 4 Complex Numbers and Quadratic Equations
EXERCISE 4.1 | Q 9. | Page 83

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