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KCET2015MathematicsProbability

If ( 1, w, w² ) are three cube roots of unity, then ( (1- + ² ) (1+ - ² ) ) is

Options

  1. A( 11 )
  2. B( 02 )
  3. C( 03 )
  4. D( 04 )

Correct answer

D. ( 04 )

Step-by-step solution

We have, (1- + ² ) (1+ - ² ) (1) We know that, 1+ + ²=0 1- + ²=-2 subtracting 2 both the sides 1+ - ²=-2 ² . subtracting 2 ² both the sides So, Eq. (1) becomes =(-2 ) (-2 ² )=4 ³=4 . Since, . ³=1

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