- Reminder: Our first exam will be next time, Friday, Fri, 2/12
- Homework 4.5 (Platonic solids) is due today
- New assignment:
Wed 2/10 Connecting the platonic solids to the golden rectangle, via Borromean Rings - No more new material before the exam
- Review: do you have any questions about material that we've
covered for the exam?
- Chapter 1: fun and games
- Sections
- 2.1: estimation
- 2.2: Fibonacci numbers
- 4.3: Golden rectangles
- 4.5: Platonic solids
- Let's finish our table of Platonic solids
- Regular polyhedra start with regular polygons (and only use equilateral triangles, squares, and regular pentagons)
The Five Convex Regular Polyhedra (Platonic solids) -- thanks Wikipedia! Tetrahedron Hexahedron
or CubeOctahedron Dodecahedron Icosahedron 
# of Vertices Edges Faces Faces at each vertex Edges at each face Tetrahedron 4 6 4 Cube 8 12 6 Octahedron 6 12 8 Dodecahedron 20 30 12 Icosahedron 12 30 20 What conclusions can we draw from this data? Is there a pattern?
- Duality
- Supplementary material:
Connecting the platonic solids to the golden rectangle, via Borromean Rings (p. 381)
- Regular polyhedra start with regular polygons (and only use equilateral triangles, squares, and regular pentagons)
- Java applets allow one to play with Platonic Solids
- A Treatise on Symmetry
- hexagonal graph paper
- Platonic Solids in 2-D (paper template)