Circles
Start off from Key Skills (for information on angles and triangles etc, not for anything specific about circles in this case)
Definitions
- Arc
- Chord
Formulae
Circumference
REmember from
Circles
tangents, angles subtended
cyclic quadrilaterals
area of circle, area of triangle
congruent similar
Angles Subtended inside a Circle
Consider an arc (or alternatively a chord) The angle subtended at the circumference by this arc is half the anglr that would be subtended by the arc at the center of the circle