Just about everything in math has a name! Did you know that a fraction of the area of a circle is known as a sector? This tutorial introduces you to the term sector and gives you examples of sectors. Take a look!
area of a sector
Know precise definitions of angle, circle, perpendicular line, parallel line, and line segment, based on the undefined notions of point, line, distance along a line, and distance around a circular arc.
Circles are a fundamental part of math! In this tutorial, you'll be introduced to circles and see the different parts of a circle such as the diameter, radius, and chord. Check out this tutorial to learn about circles!
Derive using similarity the fact that the length of the arc intercepted by an angle is proportional to the radius, and define the radian measure of the angle as the constant of proportionality; derive the formula for the area of a sector.