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Question

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\begin{document}
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\begin{flushleft}
\textbf{Universidad ICESI}\\
\textbf{Departamento de Matemáticas y Estadística}\\
\textbf{Álgebra y Funciones}\\
\textbf{Docente: \emph{Ronald Galeano}}\\
\end{flushleft}

\vspace{-3cm}
{\begin{figure}[h]
\hspace{13cm}
\begin{flushright}
\includegraphics[width=0.4\textwidth]{logoicesi}
\end{flushright}

\end{figure}
\vspace{0,5cm}
\textbf{Nombre y Código:}\\
\vspace{0,35cm}
\hspace{3.4cm} ..................................................................................\\
\vspace{0,35cm}
\hspace{3.5cm}..................................................................................\\
\vspace{0,35cm}
\hspace{3.5cm}..................................................................................\\
\vspace{0,35cm}
\hspace{3.5cm}..................................................................................

\begin{center}
\large\textbf{Taller en Clase Sección 1.3}\\
\end{center}

\begin{enumerate}
\item Lleve a cabo las operaciones indicadas y simplifique.
%\begin{multicols}{2}
\begin{itemize}
\item[A.] $(x^{3}+6x^{2}+4x+7)-(3x^{2}+2x-4)$
\vspace{0.5cm}
\item[B.] $5(3t-4)-(t^{2}+2)-2t(t-3)$
\vspace{0.5cm}
\item[C.] $x^{\frac{3}{2}}\left( \sqrt{x}-\dfrac{1}{\sqrt{x}}\right) $  
\vspace{0.5cm}
\item[D.] $(3x^{2}y+7xy^{2})(x^{2}y^{3}-2y^{2})$
\end{itemize}
%\end{multicols}
\vspace{0.5cm}
\item Factorice la expresión completamente. 
%\begin{multicols}{2}
\begin{itemize}
\item[A.] $(x-1)(x+2)^{2}-(x-1)^{2}(x+2)$
\vspace{0.5cm}
\item[B.] $(x+1)^{3}x-2(x+1)^{2}x^{2}+x^{3}(x+1)$
\vspace{0.5cm}
\item[C.] $t^{4}+t^{2}-2$
\vspace{0.5cm}
\item[D.] $2m^{3}+4m^{2}+m+2$
\vspace{0.5cm}
\item[E.] $(x-1)^{\frac{7}{2}}-(x-1)^{\frac{3}{2}}$
\vspace{0.5cm}
\item[F.] $(a^{2}+2a)^{2}-2(a^{2}+2a)-3$
\end{itemize}
%\end{multicols}



\end{enumerate}

\end{document} 

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