Difference of two squares  | English  | German  | isiXhosa

A visual explanation is explored for the observation that 2<sup>²</sup>-1<sup>²</sup>=2+1; 3<sup>²</sup>-2<sup>²</sup>=3+2 etc.
VITALmaths
The VITALmaths and VITALmathsLIC site consists of a databank of short and funky video clips that specifically interrogate the conceptual aspects of a mathematical idea, process or concept. Some of the video clips contain strategic dialogues to encourage appropriate mathematical talk and conversation.
SANDBOXmaths
SANDBOXmaths is a collection of more experimental video clips done by students in their mathematics teacher-training classes and researchers wishing to use specific video clips in their teaching and research.
APPLETmaths
The APPLETmaths site consists of a selection of GeoGebra applets that were developed by students and researchers for their research projects.