Latex Equation Challenge

latex-challenge.tex

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\begin{abstract}
    \begin{center}
        Equation Challenge
    \end{center}
\end{abstract}

    \begin{enumerate}
        \item Evaluate  $ \left(a + 3b\right)^2 \div \left(-ab\right) $ when $a = 3$ and $b = -2$.
        \item Simplify: $ \displaystyle{ \frac{x^2 + 2x - 8}{x^2 + 6x + 8} \div \frac{x^2 - 5x + 6}{5x + 10}} $ 
        \item Simplify: $ \cfrac{\cfrac{5}{3x-2} - 10}{\cfrac{4}{3x-2} + 4} $ 
        \item Solve $V = \pi r (r + h)$ for $h$.
        \item Graph the solution for $x + 1 < 5$. 
        \item Solve: 
            \begin{align*}
                 2x - y + 3z  & = 9  \\
                 -x + 2y + 2z & = 9 \\
                 x + y + z    & = 6
            \end{align*}
        \item Simplify: $\sqrt[5]{32 x^8 y^{10}}$
        \item Simplify: $\sqrt[2]{81 x^3} - 3x \sqrt{16x}$
        \item Simplify: $\left(2^{-3} x^2 y^{-1}\right) \left(2^{-1} x y^2\right)^{-2}$ 
        \item Solve for $x$: $ \log_6 x + \log_6 (x + 1) = 1 $
        \item Write $ \sin^2 x - \cos^2 x $ using only cosines.
        \item Given $\displaystyle{f(x) = \frac{2x^2}{x - 2}}$, evaluate $f(-2)$. 
        \item Let $f(x) = (2x - 1)^3$, find $f'(x)$. 
        \item Integrate: $\displaystyle{ \int_{\pi/4}^{\pi}{\frac{\sin x \, dx}{\cos x}}}$
        \item Find $\displaystyle{\sum_{n=1}^5{\frac{2^n}{n!}}}$
    \end{enumerate}

\end{document}