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Express the given complex number in the form a + ib: (-2-13i)3 - Mathematics

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Question

Express the given complex number in the form a + ib: `(-2 - 1/3 i)^3`

Sum
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Solution

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

= - `[2^3 + 3.2^2 (1/3i) + 3.2 (1/3i)^2 + (1/3i)^3]`

= `- [ 8 + 4i - 2/3 + 1/(27)i^2 i]`

= `-[22/3 + (4 - 1/27)i]`

= `[- 22/3 -107/27i]`

= - `22/3 - 107/27i`

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Chapter 5: Complex Numbers and Quadratic Equations - Exercise 5.1 [Page 104]

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NCERT Mathematics [English] Class 11
Chapter 5 Complex Numbers and Quadratic Equations
Exercise 5.1 | Q 10 | Page 104

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