(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Show that R is not isomorphic to R*.

2. Relevant equations

3. The attempt at a solution

Let f:R -> R* such that f(x) = e^x for x in R

f(a+b) = e^(a+b), but f(a)f(b) = e^(ab).

Therefore, f(a+b) != f(a)f(b).

not isomorphism.

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# Proof: Show that R is not isomorphic to R*

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