Solving a complex equation with roots of unity

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Homework Statement



z is a complex number.

Find all the solutions of

(z+1)^5 = z^5

The Attempt at a Solution



Of course one could expand (z+1)^5, but I remeber our professor solving this with roots of unity. Can anyone help?
 
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Ah, embarissing.

1=(z+1)^5/z^5
=((z+1)/z)^5

and then just using the roots of unity to find z= 1/(1-w) , w=exp(i*2k*pi/5), k=1,2,3,4.
 
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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