Attempt $1$: $10$ attempts remaining.

Find the linearization of the function $f(x,y)=\sqrt[\phantom{2}]{40-x^2-5y^2}$ at the point $(-4,2).$

$L(x,y)=$

Use the linear approximation to estimate the value of $f(-4\mathrm{.}1,2\mathrm{.}1)$

$f(-4\mathrm{.}1,2\mathrm{.}1)$~~

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