#import "../cfg.typ": *
#show: cfg

$ "Prove that" (RR, +), (RR without 0, *) "aren't isomorphic groups" $
Suppose the opposite

$(RR without 0, *) tilde.eq (RR_+, *)$

$1 = phi(1) = phi(-1^2) = phi(-1) phi(-1)$

$phi(-1) = 1 = phi(1)$

$bot$
