One Point of Inflection

The graph of every cubic function has exactly one point of inflection where the concavity changes from up to down or from down to up, and is symmetric about its inflection point. In the applet below, drag the coefficient sliders for a, b, c, and d. Notice how the coefficients change and the coordinates of the inflection point changes. Furthermore notice how the coordinates of the inflection point are always . Drag the Rotate slider and observe how the cubic function has rotation symmetry with respect to the inflection point.