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\begin{frame}
  \frametitle{Derivatives of Trigonometric Functions}
  
  \begin{block}{}
    \begin{malign}
      \frac{d}{dx} \sin x &= \cos x &&
      \frac{d}{dx} \cos x = -\sin x
    \end{malign}
  \end{block}
  \medskip

  \begin{exampleblock}{}
    Differentiate $\tan x$:
    \begin{talign}
      \frac{d}{dx} \tan x 
      &= \mpause[1]{ \frac{d}{dx} \left( \frac{\sin x}{\cos x} \right) } \\
      &\mpause[2]{= \frac{\cos x \cdot \frac{d}{dx} \sin x - \sin x \cdot \frac{d}{dx}\cos x}{(\cos x)^2}  } \\
      &\mpause[3]{= \frac{\cos x \cdot \cos x - \sin x \cdot (-\sin x)}{\cos^2 x}  } \\
      &\mpause[4]{= \frac{\cos^2 x + \sin^2 x}{\cos^2 x}  } \\
      &\mpause[5]{= \frac{1}{\cos^2 x} } \mpause[6]{\;{\color{gray} = \sec^2 x}}
    \end{talign}
  \end{exampleblock}
  \vspace{10cm}
\end{frame}