The dialog shown below is used to create the first derivative of a function. To create a derivative, you select the function you want to differentiate and use Funktion → Derivata f'(x)....

If the function is a standard function, the first derivative is the slope of the function, and it is defined as the function differentiated with respect to x: f'(x) = df(x)/dx

You can select an interval, line style, width in pixels and color for the derivative of the function. The derivative is inserted as a function and can be edited as such. The derivative will not change if you edit the original function.