\begin{frame}
  \frametitle{Linear Approximation and Differentials}
  
  \begin{center}
  \scalebox{.8}{
  \begin{tikzpicture}[default,baseline=1cm]
    \diagram{-3.5}{6}{-.5}{4}{1}
    \diagramannotatez
    \begin{scope}[ultra thick]
      \draw[cgreen,ultra thick] plot[smooth,domain=-3:6,samples=200] function{sqrt(x+3)} node[below,xshift=-2mm,yshift=-2mm] {$\sqrt{x+3}$};
      \tangent{4.5cm}{5.2cm}{pow(\x+3,.5)}{1}
      \node at(6.5,3.4) [cred,anchor=south east] {$L(x)$};
      \node[include=cred] at (1,2) {};
    \end{scope}
  \end{tikzpicture}
  }
  \end{center}
  \pause\bigskip
  
  The linear approximation is close to the curve when $x$ is near $1$.
\end{frame}