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Si
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es un cuerpo y
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\begin_inset Formula $K$
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.
Otras son
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no cuadrado y
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En ef
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status open
\begin_layout Plain Layout
a.pdf::27
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Sea
\begin_inset Formula $K$
\end_inset
un cuerpo no trivial, existe un subcuerpo
\begin_inset Formula $K'$
\end_inset
de
\begin_inset Formula $K$
\end_inset
llamado
\series bold
subcuerpo primo
\series default
de
\begin_inset Formula $K$
\end_inset
contenido en cualquier subcuerpo de
\begin_inset Formula $K$
\end_inset
, y este es isomorfo a
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si la característica de
\begin_inset Formula $K$
\end_inset
es un entero primo
\begin_inset Formula $p$
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status open
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