Geogebra is a mathematics software designed for mathematics students that creates beautiful visual outcomes – https://www.geogebra.org/
The 12-30 project https://jcdigitaljournal.wordpress.com/
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.
The 12-30 project https://jcdigitaljournal.wordpress.com/
Geogebra. 3 circles are in line. Find the size of the center circle in terms of the left and right circles.
The 12-30 project https://jcdigitaljournal.wordpress.com/
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.
The 12-30 project https://jcdigitaljournal.wordpress.com/
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).
The 12-30 project https://jcdigitaljournal.wordpress.com/
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.
The 12-30 project https://jcdigitaljournal.wordpress.com/
Geogebra. This sangaku asks to find the size of the circles in term of each other.
The 12-30 project https://jcdigitaljournal.wordpress.com/
Geogebra. This sangaku is asking to find the size of the different segments making the upper left center triangle in the large rectangle. The reasoning works just as well with a square – and it makes for an interesting design too!
The 12-30 project https://jcdigitaljournal.wordpress.com/
Geogebra. This sangaku – encapsulated in the right side RGB sphere – asks: find the size of the small circle in terms of the 3 intersecting arcs.
The 12-30 project https://jcdigitaljournal.wordpress.com/
November 22 – 326
Geogebra. . On the original tablet (cc. lower right object)2 circles of specific different sizes are inscribed in a rectangle. I put them in a cube to see what would happen and treated the image like an old litho. Geometry is an infinite source of inspiration!
The 12-30 project https://jcdigitaljournal.wordpress.com/
November 21 – 325
Geogebra. . The two forward objects on the weaving describe the problem: a right triangle , a circular arc, a square between them. Find the sizes of each object in term of each other. The center composition is the same problem in 3D – saved in a translucent box.
The 12-30 project 
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