(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data\

Find the critical points of the function. Then use the Second Derivative Test to classify each critical point (or state that the test fails).

f(x, y) = x3 + y4 - 21x - 18y2

3. The attempt at a solution

partial x derivative=3x^2-21=0

partial y= 4y^3-36y=0

i try to solve those for numbers, but the answer space in the question has space for 6 different critical point answers, so I am not sure where to go from here.

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# Finding the critical points of a multivariable function

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