Two Variable 2nd Order Taylor Series Approximation

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To derive the two-variable second-order Taylor series approximation for the function f(x,y) = x^3 + y^3 – 7xy centered at (6, -4), one must calculate the necessary partial derivatives. Begin by finding the first and second partial derivatives of f with respect to x and y, then evaluate these derivatives at the point (6, -4). Substitute these values into the Taylor series formula provided to construct the approximation. The process involves straightforward calculations and careful substitution into the Taylor series expression. Completing these steps will yield the desired approximation for f(x,y).
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Homework Statement



Derive the Derive the two variable second order Taylor series approximation,
below, to f(x,y) = x^3 + y^3 – 7xy centred at (a,b) = (6,‐4)

f(x,y) ≈ Q(x,y) = f(a,b) + \frac{∂f}{∂x}| (x-a) + \frac{∂f}{∂x}|(y-b) + \frac{1}{2!}[\frac{∂^2f}{∂x^2}| (x-a)^2 + 2\frac{∂^2f}{∂x∂y}\ |(x-a)(y-b)+ \frac{∂^2f}{dy^2}\ |(y-b)^2]

Homework Equations


The Attempt at a Solution


I do not understand the question. Please help me start out. Thanks
 
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Evaluating the Taylor expansion is pretty straightforward. All you need to do is to calculate the partial derivatives, and then evaluate them at the given point. So calculate \frac{\partial f(x,y)}{\partial x}*and then evaluate it at (x=6,y=-4). Then do the same for all other derivatives and plug the numbers you get into the expression.
 
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