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If ω is a complex cube root of unity, find the value of ω2 + ω3 + ω4. - Mathematics and Statistics

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Question

If ω is a complex cube root of unity, find the value of ω2 + ω3 + ω4.

Sum
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Solution

ω is a complex cube root of unity
∴ ω3 = 1 and 1 + ω + ω2 = 0

Also, 1 + ω2 = - ω, 1 + ω = -  ω2 and ω + ω2 = – 1

ω2 + ω3 + ω4

= ω2 (1 + ω + ω2) = ω2(0) = 0 

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Chapter 3: Complex Numbers - EXERCISE 3.3 [Page 42]

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