Solved: If a function of one variable is continuous on an
Chapter 11, Problem 11.7.30(choose chapter or problem)
If a function of one variable is continuous on an interval and has only one critical number, then a local maximum has to be an absolute maximum. But this is not true for functions of two variables. Show that the function has exactly one critical point, and that has a local maximum there that is not an absolute maximum. Then use a computer to produce a graph with a carefully chosen domain and viewpoint to see how this is possible.
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