Derivative of a Cubic - Exploration using GeoGebra

You are looking at the graph of a cubic polynomial, f(x) = x³ − 4x² + x + 6 (in blue).

The green curve is the first derivative of f(x).

Directions: Click on the point A and drag it slowly left or right. You will see the slope of the curve change as well as a trace of the point B, which is on the first derivative curve.

For an explanation of how this interactive was created using GeoGebra, see
GeoGebra math software - a review