*Observe the relationships between a function, its first derivative,
and its second derivative. Use the coordinate readout to estimate the slopes
of the graphs.*

**A pull down menu contains choices for a function f(x) , whose graph is
ghosted in a graphing window.**

**The value of x can be chosen by means of a slider under the window.
The [>>] key initiates an animation, by smoothly increasing the value of x.
The [<<] key resets x to its minimal value.**

**The graph of f(x) is displayed in cyan. Check boxes toggle display of
graphs of f '(x) (in red) and f "(x) (in green) for values
of x less than its chosen value.
Further check boxes toggle display of the tangent line and of the approximating parabola.**

**A readout displays the current values of f(x), and of f '(x) and f "(x) if
selected.**

**Rolling the mouse over the graphing window creates crosshairs and a readout
of the values of x and y . Depressing the mousekey suppresses this readout.**

**© 2010 H. Miller, H. Burgiel, and J.-M. Claus**