Capítulo 10 · Neste capítulo você vai
Circumference and circle
- distinguish circumference from circle and know chord, arc, sector and segment;
- classify the positions of straight line and circle and two circles;
- use the tangent segments property;
- recognize quadrilaterals circumscriptible (Pitot theorem).
The circumference has fascinated mathematicians since ancient times. The ratio of length to diameter, the number $\pi$, was estimated by Archimedes in the 3rd century BC with unprecedented precision (see chapter 17). Waves on the water, wheels, gears and glasses show how it is everywhere.
