\begin{frame} \frametitle{Exponential Functions: The Number $e$} \begin{block}{} The number \begin{talign} e \approx 2.71828\ldots \end{talign} is a very special base for exponential functions. \end{block} \pause\bigskip \begin{minipage}{.49\textwidth} \begin{center} \scalebox{.8}{ \begin{tikzpicture}[default,baseline=0cm] \diagram{-2.5}{1.5}{-.5}{4}{1} \diagramannotatez \diagramannotatexx{-1,1} \diagramannotatey{1} \begin{scope}[ultra thick] \draw[cgreen] plot[smooth,domain=-2.5:1.4,samples=300] (\x,{e^\x}); \end{scope} \begin{scope}[dashed,thick] \tangent{2.5cm}{2.5cm}{e^\x}{0} \node[include=cred] at (0,1) {}; \end{scope} \end{tikzpicture} }\\[.5ex] tangent has slope $1 = e^0$ \end{center} \end{minipage} \begin{minipage}{.49\textwidth} \begin{center} \scalebox{.8}{ \begin{tikzpicture}[default,baseline=0cm] \diagram{-2.5}{1.5}{-.5}{4}{1} \diagramannotatez \diagramannotatexx{-1,1} \diagramannotatey{1} \begin{scope}[ultra thick] \draw[cgreen] plot[smooth,domain=-2.5:1.4,samples=300] (\x,{e^\x}); \end{scope} \begin{scope}[dashed,ultra thick] \tangent{3.5cm}{1.5cm}{e^\x}{1} \node[include=cred] at (1,{e}) {}; \end{scope} \end{tikzpicture} }\\[.5ex] tangent has slope $e = e^1$ \end{center} \end{minipage} \pause \begin{block}{} The slope of the function $e^x$ at point $(x,e^x)$ is $e^x$. \end{block} \end{frame}