Math and circles

I was working on an AutoCAD drawing at work, and started looking around for geometric solutions for tangent circles (despite what one might expect, AutoCAD can’t do everything). Next thing I know, I’m looking at proofs for inversion geometry. Check out this fantastic site for some great geometric demonstrations. I was particularly impressed with the inversion geometry, as soon as I realized that it is a general mathematical solution for reflected images on curved surfaces, as well as a geometric transformation for difficult geometric proofs. He makes extensive use of the Geometer’s Sketchpad which you may want to look into as well if you’re interested in geometry. Of course, if you’re really interested in geometry, or just don’t like shelling out money, get KSEG for free!