$S={x+\sqrt[3]{2}y: x,y \in \Q}$
agile mist
$S={x+\sqrt[3]{2}y: x,y \in \Q}$
molten anchorBOT
pallid hollyBOT
rabbits_advocate
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agile mist
Can anyone explain why S is not a field?
final jetty
Not closed under multiplication, e. g. Doesn't have $\sqrt[3]{4}$