Find all the values of (-2+2i)^(1/3)

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Homework Statement



Find all the values of (-2+2i)1/3

Homework Equations



eib = cos(b) + i * sin(b)

The Attempt at a Solution





(-2+2i)1/3 = (2(-1+i))1/3 = 21/3 (√2)1/3 (eiπ(3/4 + 2m))1/3 = 21/2 (eπi)1/4 + 2m/3 = ... Where am I going with this? I don't even know.
 
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You need to use the definition:

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

where \theta is the argument of u
 
Jamin2112 said:

Homework Statement



Find all the values of (-2+2i)1/3

Homework Equations



eib = cos(b) + i * sin(b)

The Attempt at a Solution





(-2+2i)1/3 = (2(-1+i))1/3 = 21/3 (√2)1/3 (eiπ(3/4 + 2m))1/3 = 21/2 (eπi)1/4 + 2m/3 = ... Where am I going with this? I don't even know.
Change it back to a+bi form using m=0,1,2 .
 
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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