This is a GeoGebra applet for demonstrating the graphical relationship between a cubic and its first and second derivative.
I have attached a version optimized for 1280x800 resolution, and also a version that is optimized for use on an IWB.
It is a highly visual tool, all of the co-efficients of the cubic curve are controlled via sliders to show the constantly variable relationship between a curve and its derivatives.
The derivative curves (and tangents to these curves) can be turned on and off via a series of checkboxes on the screen. All tangents can be moved around the curves to demonstrate gradients, points of inflexion etc etc.
Download and enjoy!
16 November 2012 Edit: 28 February 2014
Shared by Ciaran Quinn 1