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user131753
12:16 PM
$\require{AMScd} \begin{tikzcd}
A \arrow[r, "f"] \arrow[d, "h"] & B \arrow[d, "g"] \\
C \arrow[r, "i"] & D
\end{tikzcd}$
 
user131753
$\require{AMScd}$
\begin{CD}
A @>a>> B\\
@V b V V= @VV c V\\
C @>>d> D
\end{CD}
 
user131753
$\require{AMScd}$
\begin{CD}
A @>a>> B\\
@V b V V @VV c V\\
C @>>d> D
\end{CD}
 
user131753
$$G\simeq$$
 
user131753
$$G\approx H$$
 

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