\begin{frame} \frametitle{2nd Midterm Exam - Review} \begin{exampleblock}{} Find an equation for the tangent at point $(3,-2)$ to the curve\vspace{-1.2ex} \begin{minipage}{.59\textwidth} \begin{align*} y^2(y^2-4) = x^2(x^2-9) \end{align*} \onslide<2->{ We have\vspace{-1.2ex} \begin{align*} y^4 - 4y^2 = x^4-9x^2 \end{align*} } \end{minipage} \begin{minipage}{.39\textwidth} \vspace{2ex} \includegraphics[scale=.6]{../devil.png} \vspace{-2ex} \end{minipage}\vspace{-2ex} \pause\pause We use implicit differentiation\vspace{-1.2ex} \begin{align*} &\frac{d}{dx} (y^4 - 4y^2) = \frac{d}{dx} (x^4-9x^2)\\ &\mpause[1]{\implies\; 4y^3y' - 8yy' = 4x^3-18x}\\ &\mpause[2]{\implies\; y'(4y^3 - 8y) = 4x^3-18x}\\ &\mpause[3]{\implies\; y' = \frac{2x^3-9x}{2y^3 - 4y}} \mpause[4]{ = \frac{2\cdot 3^3-9\cdot 3}{2(-2)^3 - 4\cdot (-2)}} \mpause[5]{ = \frac{54-27}{-16 + 8}} \mpause[6]{ = -\frac{27}{8}} \end{align*} \pause\pause\pause\pause\pause\pause\pause Thus the equation for the tangent is \quad \alert{$y + 2 = -\frac{27}{8}\cdot (x-3)$}. \end{exampleblock} \end{frame}