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\ExamClass{Котов Егор}
\ExamName{Математическая статистика}
\ExamHead{\today}

\let\ds\displaystyle

\begin{document}

\begin{enumerate}
   \item $f(x) = e^{-a|x|}cos(bx)$
      \begin{enumerate}
	 \item $\ds{\lim_{x\rightarrow3}\frac{\sqrt{x+1} - 2}{x-3}}$
	 \item $\ds{\lim_{x\rightarrow0}\frac{\sin(4x)}{8x}}$
      \end{enumerate}
   \item Use the $\varepsilon$-$\delta$ definition of limit to prove that
      \[\lim_{x\rightarrow 2} x^2 - 3x + 2 = 0\]\noanswer[2.5in]

\end{enumerate}
\end{document}