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	{\noindent 21-120 Differential and Integral Calculus \hfill Summer Session I 2010\\}
	{\centering Quiz 1 \medskip\\}
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	{
		\renewcommand{\theenumi}{(\alph{enumi})}
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	\begin{prob*} Factor the following:
		\begin{enumerate}
			\item $x^4 - 16$
			\item $2x^2 - 4x + 2$
			\item $x^3 - x^2 - 2x$
		\end{enumerate}
	\end{prob*}
	\begin{soln*} \mbox{}
		\begin{enumerate}
			\item \begin{align*}x^4 - 16\\ &= (x^2)^2 - (4)^2\\&= (x^2 - 4) (x^2 + 4)\\&= (x-2)(x+2)(x^2+4)\end{align*}
			\item \begin{align*}2x^2 - 4x + 2\\ &= 2(x^2 - 2x + 1)\\ &= 2(x-1)(x-1)\end{align*}
			\item \begin{align*}x^3 - x^2 - 2x\\ &= x(x^2 - x - 2)\\ &= x(x-2)(x+1)\end{align*}
		\end{enumerate}
	\end{soln*}
	}


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