Complex Analysis: Express f(z)= (z+i)/(z^2+1) as w=u(x,y)+iv(x,y)

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Homework Statement


write f(z)= (z+i)/(z^2+1) in the form w=u(x,y)+iv(x,y)


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The Attempt at a Solution


I tried using the conjugate and also expanding out algebraically but I can not seem to get the right answer. I know what the answer is, x/(x^2+(y-1)^2)+i(1-y)/(x^2+(y-1)^2) but I fail to see how to get there. am I doing something wrong?
 
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all i want is a simple hint i don't want anyone to do the problem for me I just want a little help. just a little push in the right direction would be so helpful.
 
Why don't you try and do the partial fraction. I think it should work.
 
rizardon said:
Why don't you try and do the partial fraction. I think it should work.

So I do the partial fraction after i expand out? expanding (z+i)/(z^2+1) I get (x+yi+i)/(x^2+2xyi-y^2+1) how am I supposed to factor the denominator?
 
ohhhhh nevermind i finally got it you rewrite the denominator as (z+i)(z-i) then do the partial fraction. so simple! you were right rizardonthanks
 
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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