Jane really appreciates the great optical illusions and Escher-art book suggestions. She has added more than a few promising titles to her birthday wish list, so perhaps we’ll have some reviews to share in the months ahead. In the meantime, here’s a nifty YouTube clip we found. Jane was looking for help in drawing “impossible shapes”; I didn’t know what she meant until she showed me pictures in the Harold Jacobs Mathematics book. (Highly recommended, by the way—we have never used the Jacobs books as textbooks, but rather they have been ‘fun reading’ for Jane and others for several years. She has Mathematics: A Human Endeavor and the algebra book, and actually the Jacobs geometry book is item number one on her birthday list.)
Back to the video clip. Jane spent a good bit of time yesterday working out how to draw the “impossible triangle.” This morning we found this Paint tutorial demonstrating that triangle and several other “impossible” shapes. Simple and fun.