- ratio
- a definition of conics (directrix)
- ratio of areas-1
- right triangle trigonometry-2
- regular polygons-1
- right triangle trigonometry-1
- the golden ratio
- ptolemy's theorems
- find the slope
- areas of similar triangles
- όμοιες ελλείψεις
- measuring van gogh's cypress
- pythagorean and galileo's law
- the angle bisector theorems
- trig values of any angle
- the golden ratio (and aphrodite's phi)
- approximating pi
- ratio of areas-2
- division of a segment
- an apollonian circle
- law of sines (proof)
- yin-yang
- the famous "1/7" triangle
- right triangle trigonometry-2
- approximating pi...
- the golden ratio and aphrodite's phi
- right triangle trigonometry
- circumference of circles-1
