- CirclesCircumference of CirclesArea of CirclesExploring the Equation of a CircleCircle with Center and RadiusProperty of a tangentDefinition of TangentRolling Coin 滾動的硬幣circle theorem 1aRadius perpendicular bisector of chordCircles & Their line segmentsCircle Theorem 1 - Angle at the CentreCircle Theorem 2 - Angles in a SemicircleCircle Theorem 3 - Angles in the Same SegmentCircle Theorem 4 - Cyclic QuadrilateralCircle Theorem 5 - Radius to a TangentCircle Theorem 6 - Tangents from a Point to a CircleCircle Theorem 7 - Tangents from a Point to a Circle IICircle Theorem 8 - Alternate Segment TheoremArea of CirclesArea of a Circle - Wedge/Sector DemonstrationSine and Cosine Components
