Vault Of Euclid

Finding Relative Extrema of a Quadratic Function of Two Variables

Partial derivatives warmup

Find all relative maxima and minima of \( f(x, y) = x^2 + 2xy + 2y^2 \).
multivariable-calculuspartial-derivativescritical-pointsrelative-extremaabsolute-minimumcompleting-the-squareoptimizationquadratic-formfind-minimumfind-maximum

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What you need first

What this problem tests

Tests the ability to compute partial derivatives, find critical points, and use algebraic manipulation (completing the square) to classify extrema.

This problem is typical of an introductory multivariable calculus course, introducing optimization of functions of two variables.