Here are examples of dynamic software modelling enlargement and negative enlargement. You can explore these yourself by downloading free files below together with free trials of the software with which to manipulate them (Cabri Geometry II Plus, The Geometer's Sketchpad and Autograph 3).
Please note: Cabri Geometry II files are text files. If, when you click on the Cabri file links, your browser window fills with text, either save it as a text file with the .fig extension, or alternatively right-click to download the file, choosing to "save as" to your PC.
To manipulate the above ray visualiser yourself, download the file 'RayVisualiser1.fig' (right click on this link and choose to 'save as' to your PC). Open the file with the program 'Cabri Geometry II Plus' (free trial downloadable from this link.) Alternatively, download the file RayVisualiser1.gsp and open it with the program The Geometer's Sketchpad (free trial downloadable from this link.)
To manipulate files the files used to create the movies below click on the named link for the software you use.
Please note that this site uses Flash Player to display moving images. If you can't see the moving images you may not have the Flash Player plug-in installed on your computer. To install the Flash Player please go to http://www.macromedia.com/shockwave/download/download.cgi?P1_Prod_Version=ShockwaveFlash