The second directional derivative of $f(x, y)$ is $D_u^2f(x, y) = D_u[D_uf(x, y)]$. If $f(x, y) = x^3 + 5x^2y + y^3$ and $u = \left<\frac{5}{13}, \frac{12}{13}\right>$, calculate $D_u^2f(3, 2)$. $D_u^2f(3, 2) = $
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$$\nabla f(x,y) = \left\langle \frac{\partial f}{\partial x}, \frac{\partial f}{\partial y} \right\rangle = \left\langle 3x^2 + 10xy, 5x^2 + 3y^2 \right\rangle$$ Show more…
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The $ \textbf{second directional derivative} $ of $ f(x, y) $ is $$ D_u^2 f(x, y) = D_u [ D_u f(x, y) ] $$ If $ f(x, y) = x^3 + 5x^2y + y^3 $ and $ u = \langle \frac{3}{5}, \frac{4}{5} \rangle $, calculate $ D_u^2 f(2, 1) $.
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The second directional derivative of $f(x, y)$ is $$D_{\mathrm{a}}^{2} f(x, y)=D_{\mathrm{a}}\left[D_{\mathrm{a}} f(x, y)\right]$$ If $f(x, y)=x^{3}+5 x^{2} y+y^{3}$ and $\mathbf{u}=\left\langle\frac{3}{5}, \frac{4}{5}\right\rangle,$$ calculate $ D_{\mathbf{u}}^{2} f(2,1)$$
The second directional derivative of f(x, y) is Du^2f(x, y) = Du[Duf(x, y)]. If f(x, y) = x^3 + 5x^2y + y^3 and u = [3/5, 4/5], calculate Du^2f(2, 1). Du^2f(2, 1) =
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