Visualization in Mathematics using Geometer's Sketchpad

Jon Wilkin, Northern Virginia Community College.  www.nvcc.edu/home/jwilkin 

These models require the user have The Geometer's Sketchpad, version 4, installed on their computer. The software is available from the publisher at www.keypress.com 

Conics

parabola - traces a parabola in standard position with the focus on the y-axis.

parabola_general - traces a parabola using the focus-directrix definition. Either the focus or the directrix can be moved.

ellipse - traces an ellipse being created using the "sum of distances from foci is constant" definition. Either foci can be moved and the sum distance can be changed.

hyperbola - traces a hyperbola being created using the "difference of distances from foci is constant" definition. Either foci can be moved and the difference distance can be changed.

conics - graphs conics using polar coordinates, showing the variation as eccentricity changes from 0 to 2.