Nice, but the Derivatives are buggy!!!

Appears okay for basic graphing, however, if using this app for Calculus, the app doesnt do a reliable job of computing derivatives.

For example, the "example" derivative in the app library is incorrect ( both the graph and computed derivative appear incorrect).

The example is y=n * d/dx (sin(x) - cos(x))^2
and the app gives the result as...
y= n * cos(x) - - sin(x)^2 which is incorrect. Too bad the developers didnt check this example before releasing a potentially nice feature.

The app seems to compute simple derivatives just fine. Users be careful until this situation is corrected.

Neptue about Quick Graph+