\begin{frame} \frametitle{Limit: Examples} \begin{exampleblock}{} Guess the value of \begin{talign} \lim_{x\to 1} \frac{x-1}{x^2-1} \end{talign} \end{exampleblock} \pause \medskip \begin{minipage}{.43\textwidth} \scalebox{.6}{ \begin{tikzpicture}[default] \diagram{-1}{5}{-1}{5}{1} \diagramannotate \draw[cblue,ultra thick] plot[smooth,domain=-.8:4.5,samples=20] (\x,{(\x-1)/(pow(\x,2)-1)}); \def\x{1} \def\y{{.5}} \begin{scope}[dashed,cred,ultra thick,inner sep=1mm] \draw (\x,\y) -- (\x,0mm); % \draw (\x,\y) -- (-2mm,\y) node [left] {$L$}; \end{scope} \node[exclude={cblue}] at (\x,\y) {}; % \node[include={cblue},yshift=-10mm] at (\x,\y) {}; \end{tikzpicture} } \end{minipage} \begin{minipage}{.56\textwidth} \pause The function is not defined at $x=1$.\\ \pause (does not matter for the limit) \bigskip \pause \begin{minipage}{.49\textwidth} from below:\\[.5ex] {\small \begin{tabular}{|l|l|} \hline $x$ & $f(x)$ \\ \hline $0.5$ & $0.66667$ \\ \hline $0.9$ & $0.52632$ \\ \hline $0.99$ & $0.50251$ \\ \hline $0.999$ & $0.50025$ \\ \hline \end{tabular} } \end{minipage}\pause~~~ \begin{minipage}{.49\textwidth} from above:\\[.5ex] {\small \begin{tabular}{|l|l|} \hline $x$ & $f(x)$ \\ \hline $1.5$ & $0.40000$ \\ \hline $1.1$ & $0.47619$ \\ \hline $1.01$ & $0.49751$ \\ \hline $1.001$ & $0.49975$ \\ \hline \end{tabular} } \end{minipage} \end{minipage} \pause \begin{exampleblock}{} From these values we guess that $\lim_{x\to 1} \frac{x-1}{x^2-1} = 0.5$. \end{exampleblock} \end{frame}