Factor Ring of a Ring: Example of Integral Domain with Divisors of 0

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Homework Statement


give an example to show that a factor ring of a ring with divisors of 0 may be an integral domain.


Homework Equations


since we know that ZxZ is a zero divisor and 5Z is an integral domain.


The Attempt at a Solution


So, ZxZ/5Z =~(isomorphic to) Z/5Z=~ Z_5.
 
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ZxZ/5Z doesn't even make much sense. 5Z isn't a subring of ZxZ.
 
I forgot about that.. let try Z/ZxZ =~ Z Since ZxZ is a subring of Z.
 
tinynerdi said:
I forgot about that.. let try Z/ZxZ =~ Z Since ZxZ is a subring of Z.

How are you considering ZxZ as a subring of Z? ZxZ is ordered pairs of integers, isn't it? Z is just integers.
 
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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