4 ms·
In the first sentence, I didn't talk about the difference quotient, just plain f.
by posterboy 9y ago
In the first sentence, I didn't talk about the difference quotient, just plain f.
- yequalsx 9y agoI see. Then I don't understand what point you were trying to make. There are lots of different ways of testing understanding of a concept. I presented one way of doing so with students having access to a computer.
- posterboy 9y agoI was saying you presented a weak argument. Graphing the differentialquotient multiple times is more trouble than it's worth.
- yequalsx 9y agoThe point of the problem I gave was not to find the derivative or even to know if a function is differentiable. The point is to test their understanding of the definition of derivative. It's a good problem in that is tests whether a student understands that in the two variable expression we call the difference quotient one of the variables is fixed for purposes of the definition. The students need to know that it is h that varies and not x. This is an unusual occurrence and requires some getting used to.