Find value of $(5 + 2 w + 5 w^{2})$ , where $w$ - an imaginary cube root of unity.

- 3 w

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Solution

The correct option is A $- 3 w$
Given,

$5 + 2 w + 5 w^{2}$

w.k.t $1 + w + w^{2} = 0$

$= 2 w + 5 (1 + w^{2})$

$= 2 w + 5 (- w)$

$= 2 w - 5 w$

$= - 3 w$

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