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\section{askisi orion}
na ypologisti to orio:
\begin{equation}
          \lim_{x \to 2}\frac{x^2-4}{x-2}
\end{equation}
\subsection*{lisi}
paratiroume oti av avtikatastisoume to $x$ me $2$ ,exoume

$\frac{0}{0}$ , pou einai aprosdioristi morfi.Epomenos prepei va aplopoihsoume thn ekfrash.

\begin{equation}
          \lim_{x \to 2} \frac{x^2-4}{x-2}=
          \lim_{x \to 2} \frac{(x-2)(x+2)}{x-2}
\end{equation}
aplopoiontas ton koino paragoda $x-2$, exoume:
\begin{equation}
         \lim_{x \to 2}(x+2)
\end{equation}
tora antikathistontas to $x$ me $2$:
\begin{equation}
          \lim_{x \to 2} \frac{x^2-4}{x-2}=4
\end{equation}          
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