\begin{frame}
\frametitle{Logarithmic Differentiation}
\begin{exampleblock}{}
Differentiate
\begin{talign}
y = x^{\sqrt{x}}
\end{talign}
\pause
The power rule does not apply: the exponent contains $x$!
\pause\medskip
We use logarithmic differentiation:
\begin{talign}
&\ln y = \ln \left(x^{\sqrt{x}}\right) = \mpause[1]{\sqrt{x} \cdot \ln x} \\
&\mpause[2]{ \frac{d}{dx} \ln y = \frac{d}{dx } \left( \sqrt{x} \cdot \ln x \right) }\\
&\mpause[3]{ \frac{1}{y}y' = \sqrt{x}\cdot \frac{1}{x} + \ln x \cdot \frac{1}{2\sqrt{x}} }\\
&\mpause[4]{ y' = y\left( \frac{1}{\sqrt{x}} + \frac{\ln x}{2\sqrt{x}} \right) }
\mpause[5]{= y\left( \frac{2+ \ln x}{2\sqrt{x}} \right) }
\mpause[6]{= x^{\sqrt{x}} \left( \frac{2+ \ln x}{2\sqrt{x}} \right) }
\end{talign}
\pause\pause\pause\pause\pause\pause
\end{exampleblock}
\pause\medskip
Alternative:
\quad $x^{\sqrt{x}} \mpause[1]{ = (e^{\ln x})^{\sqrt{x}}} \mpause[2]{ = e^{\ln x \cdot \sqrt{x}}}$\quad
\pause\pause\pause now use chain rule
\bigskip
\end{frame}