Question
Find $D_{\mathfrak{u}} f$ at $P$.$$\begin{array}{l}{f(x, y, z)=\ln \left(x^{2}+2 y^{2}+3 z^{2}\right) ; P(-1,2,4)} \\ {\mathbf{u}=-\frac{3}{13} \mathbf{i}-\frac{4}{13} \mathbf{j}-\frac{12}{13} \mathbf{k}}\end{array}$$
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The gradient of a function is a vector that points in the direction of the greatest rate of increase of the function, and its magnitude is the rate of increase in that direction. The gradient of $f$ is given by the vector of its partial derivatives with respect to Show more…
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