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missing a critical point #951

Closed pfatheddin closed 8 months ago

pfatheddin commented 8 months ago

See maximumsAndMinimums/exercises/maxMinSecondDerivativeTest4.tex

https://ximera.osu.edu/mooculus/maximumsAndMinimums/exercises/exerciseList/maximumsAndMinimums/exercises/maxMinSecondDerivativeTest4?

Here it says the function only has one critical point: image

But if you find the derivative you get: image They have 8/3 but also need 4 since by definition is a critical point.

bwramsey commented 8 months ago

The point at x=4 does NOT satisfy the definition of being a critical point. (Not an interior point of the domain.)