Prove Nth Roots of Unity: \omega, \overline{\omega}, \omega^{r}

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Homework Statement


Show that, if \omega is an nth root of unity, then so are \overline{\omega} and \omega^{r} for every integer r.


Homework Equations


\omega=r^{1/n}e^{i((\theta+2\pi)/n)}


The Attempt at a Solution


I got the first part and for \omega^{r} I have it equals
e^{i(r2\pi/n)}
but what more do I need to do/show to prove it's an nth root of unity?
 
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There's no need to use an explicit form for w. An nth root of unity satisfies w^n=1. Just use that. Take the conjugate and then raise both sides to the power r.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...

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