If a complex converges, then it's conjugate converges.

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Homework Statement



Prove that z_n -> z_0 if and only if ~(z_n) -> ~(z_0) as n goes to infiinity.

~(z_n) is the conjugate of z_n.


Homework Equations





The Attempt at a Solution



|~(z_n) - ~(z_0) | = | ~(z_n) + ~(-z_0)| <=

|~(z_n)| + |~(-z_0) | = |z_n| + |z_0| <=

and I can't come up with much else. It's about the same for the other direction as well.
 
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Using a '*' for complex conjugation is more usual than '~'. |z*|=|z|.
|z_n*-z_0*|=|(z_n-z_0)*|=|z_n-z_0|. Use stuff like that. Now write it in the form of a proof about limits.
 
Dick said:
Using a '*' for complex conjugation is more usual than '~'.

* looks better after seeing it. I just couldn't think of a way the first time around.
 
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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