Mathigon
Mathigon: Geometry: Circle and Pi: Introduction
This lesson focuses on the characteristics of a circle including similarity, radius, circumference, and Pi. It provides formulas to determine the area of a circle, calculating Pi, and learning exercises throughout.
Mathigon
Mathigon: Geometry: Circle and Pi: Conic Sections
The circle is one of four different shapes which can be created using "slices" through a cone, a 3-dimensional solid that has a circular base joined to a single point (called the vertex) by a curved side. If you tilt a cone, you get an...
Mathigon
Mathigon: Geometry: Circle and Pi: Degrees and Radians
Rather than dividing a circle into some number of segments (like 360 degrees), mathematicians often prefer to measure angles using the circumference of a unit circle - a circle with radius 1. This way of measuring angles is called...