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Viewing Version 3 of 'linear isomorphism'
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Title of object: linear isomorphism
Canonical Name: LinearIsomorphism
Type: Definition

Created on: 2004-09-17 13:23:34
Modified on: 2004-10-17 10:54:29

Creator: matte
Modifier: CWoo
Author: matte

Classification: msc:15A04
Synonyms: linear isomorphism=invertible linear map
linear isomorphism=bijective linear map
linear isomorphism=non-singular linear map

Revision comment (for changes between this and next version):

Changes for correction #14631 ('U, V... and W?').

Preamble:

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Content:

\begin{defn}
Suppose $V$ and $W$ are vector spaces and $L\colon U\to V$ is a linear map.
Then $L$ is a \emph{linear isomorphism} if $L$ is bijective.
\end{defn}

\subsubsection*{Properties}
\begin{enumerate}
\item Compositions and of linear isomorphisms is a linear isomorphism.
\item The inverse of a linear isomorphisms is a linear isomorphism.
\item If either $U$ or $V$ if finite dimensional, then $\dim V=\dim W$.
(This is a consequence of the rank-nullity theorem.)

\end{enumerate}