Sangaku Circle-Triangle-Circle-Square
Sangaku Circle-Triangle-Circle-Square
1. The large circle is internally tangent to the square.
2. The two small circles are tangent to this circle and the square.
3. The triangle is tangent to the two small circles.
4. The midsize circle is the incircle of the triangle.
Compare the radius of the midsize circle to the radius of the large circle.
(H.Okumura)
http://www.hermay.org/jconstant/wasan/sangaku/index.html