Homework Statement
Let R = Z7[x]. Show that R is not isomorphic to Z.
Homework Equations
The Attempt at a Solution
One of the necessary conditions for an isomorphism f is that f be one to one. So consider 8x in Z. f(8x) = x, f(1x) = x. So f cannot be an isomorphism. I'm clearly missing...
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On the other hand, you might consider learning Clojure. Common Lisp is really...