cube roots of unity

if 1,w w² are cube roots of unity,then the value of(1+w²-w)(1-w²+w)

2 Answers

262

Aditya Bhutra ·2011-06-15 03:12:19

(1+w2-w)(1-w2+w)
=(-w-w)(-w² -w² )..... (since 1+w+w² =0)
=-2w * -2w²
=4

Use the property that

1+w+w² = 0 and w³ = 1

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