7. Root 2 as a continued fraction

9. J. H. Conway, R. K. Guy, The Book of Numbers, Copernicus, 1996The Book of Numbers

10. Trisecting an angle Trisecting an angle Squaring the circle Squaring the circle Doubling the cube Doubling the cube Squaring the circle Doubling the cube Trisecting the angle

11.  circumference/diameter

12. Pi =circumference/diameter Circumference=pi x diameter Diameter=2 x radius Circumference =2 pi r For a unit diameter circle circumference = pi

21. Nova Infinite Secrets Interactive

32. Link