Understanding Multivariable Calculus: Problems, Solutions, and Tips
Extrema of Functions of Two Variables
S1 E6:
The ability to find extreme values for optimization is one of the most powerful consequences of differentiation. Begin by defining the Extreme Value theorem for multivariable functions and use it to identify relative extrema using a “second partials test,” which you may recognize as a logical extension of the “second derivative test” used in Calculus I.