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\begin{document}
\section{askisi paragogon}
na ypologisti h paragogos ths sinarthshs:
\begin{equation}
          f(x)=x^3+2x^2-5x+3
\end{equation}
\subsection*{lisi}
xrisimopoioume tous kanones paragwgishs:
\begin{align}          
          f'(x)&= \frac{d}{dx}(x^3) + \frac{d}{dx}(2x^2)
          - \frac{d}{dx}(5x) + \frac{d}{dx}(3)\\
          &=3x^2+4x-5+0
\end{align}

\end{document}

