From Latin: sector "a cutter"
Definition: The part of a circle enclosed by two
of a circle and their
A pie-shaped part of a circle.
Try this Drag one of the orange dots that define the endpoints of the blue arc.
The sector of the circle is shown in yellow.
As you can see from the figure above, a sector is a pie-shaped part of a circle. It has two straight sides (the two radius lines),
the curved edge defined by the arc, and touches the center of the circle.
The area of a sector can be found if you know the radius and the central angle or arc length.
For more on this see Area of a sector.
Other circle topics
Equations of a circle
Angles in a circle
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