Miscellaneous Bugs and Problems

[jte]

(11-25-2016 05:10 AM)CH3791 Wrote:  1a. Plotting the derivative of a function in the function app.
...
For these two cases, most of the functions would not work correctly. The ones with problems I have found include: 6 Slope, 7 Signed Area, 8 Extremum, 9 Tangent

The Slope, Extremum, and Tangent features of the Function Plot view ask lower levels of the system to differentiate the function of interest. There are a variety of conversion issues involved.

If you go to the CAS screen and try entering
   diff(F2(X),X)
with F1 and F2 defined as you've suggested (F1(X)= X^3+3*X^2 and F2(X)= ∂(F1(X),X=X)), you'll see this (conversion) issue at a command-line level.

Similarly, an evaluation of
   ∫(F2(X),X,0,1)
in the CAS screen will show this type of conversion issue at a command-line level for integration (which the Signed Area feature of the Function app relies on).