How to interpret quotient rings of gaussian integers

nateHI
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Homework Statement



This is just a small part of a larger question and is quite simple really. It's just that I want to confirm my understanding before moving on.

What are some of the elements of Z<i>/I</i> where I is an ideal generated by a non-zero non-unit integer. For the sake of argument, let's take I=<3>.

Homework Equations


The Attempt at a Solution


Representatives from one coset would be the following...
(8+4i)/<3>=(5+i)/<3>=(2+i)\in Z<i>/&lt;3&gt;</i>

Representatives from another coset would be the following...
(7+5i)/<3>=(4+2i)/<3>=(1+2i)\in Z<i>/&lt;3&gt;</i>
 
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At first glance I think it would be \mathbb{Z}_3. Can you try to prove this?
 
http://www.math.uconn.edu/~kconrad/blurbs/ugradnumthy/Zinotes.pdf

I found the answer in that link on page 17. You are correct the elements are isomorphic to the integers mod 3 adjoin i. I just didn't understand that the quotient ring I was trying to produce the elements of was the (integers adjoin i) mod the generator of the ideal.
 
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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