Wednesday, February 5, 2014

Class #5

Class #5

- Reminder to read Flatland.
- Look over reading and assignments

- Reflection Symmetry across a vertical or horizontal line.

- Rotational symmetry by 180 degrees.

Miscellaneous: Some topics we will study (

- Symmetry.
- Tiling.

- The Sphere and the Torus. Surfaces
- Proof and Truth in Geometry and Arithmetic.

The triangles are not similar: the green/purple triangles have sides 3 by 8 while the triangle in the quadrilaterals have sides 2 by 5. Therefore they do not combine to have a right angle in the corners of the 5 by 13 figure.

Theme Question: Who first showed the
earth was a sphere or shaped like a sphere?

- More discussion on the The Sphere, The Plane, and the Torus.

Question 1. How can one ** distinguish the sphere from a plane**
(Flatland) based solely on
experiences on the surface?

Question 2. How can one

**Activity: Tile plane with playing cards.**