The n^ th roots of unity are in

Let $x = 1$

$= \cos 0 ° + isin0 °$

$⇒ x^{1 / n} = e^{i\left(2\pir\right) / n}; r = 0, 1, 2, \ldots$

Then, the roots are $1, e\dfrac{2\pii}{n}, e\dfrac{4\pii}{n}, \ldots$ which are clearly on $GP$ with common ratio $e^{2\pii / n}$