Sangaku are geometrical problems carved on wooden tablets. They were very popular in Japan during the Edo period (1603-1867).
Sangaku was the theme for the 12-30 project, month of November. I compiled the entire series with additional artworks inspired by the Sangaku tradition in one volume including over 60 illustrations, the original geometry they originated from, along with their mathematical description and possible solution
The book is now available in electronic format on the iBook store, GoogleBook, and Kindle. The individual images, large size print on canvas on SaatchiArt.
The 12-30 project, animated HD for the month of November “Current Sangaku” – is now on Vimeo. Images of the sequence were originated in Geogebra. Additional credits: Yutaka Yamada, Derek & Brandon Flechter for the music.
November 30– 334.
Geogebra. Ending the month with one last template from the Fukagawa/Rothman book on Japanese temple geometry – the Abe no Monjuin sangaku.
The tablet asks to find the radius of the small circles in terms of the sides of the triangles.
November 29– 333
Geogebra. 3 circles are in line. Find the size of the center circle in terms of the left and right circles.
November 28 – 332.
Geogebra. The original sangaku tablet asked to find the size of the larger cube in terms of the two spheres – as in the lower right part of the image.
November 27 – 331.
Geogebra. This sangaku is intriguing because of the symmetrical aspect of its geometry. It asks to find the diameter of the smallest circle(s) in terms of the central circle(s).
November 26 – 330.
Geogebra. A sangaku that asked to find the size of the small green circles in terms of the largest (red) minus the smallest (blue) circles.