Circles - Mathematics
- Equation of circle in various forms
- Radius and centre of equation of circle in various forms
- Condition on equation of second degree to represent circle
- Position of a point w.r.t. a circle
- Parametric equation of a circle
- Tangent
- Normal
- Condition of tangency
- Chord of contact
- Equation of chord with midpoints
- Pair of tangents
- Length of tangent
- Condition for two circles touching each other
- Condition for two circles touching and intersecting each other
- Family of circles - passing through point of intersection of two circles
- Family of circles - passing through point of intersection of line and a circle
- Family of circles - passing through two points
- Family of circles - always touching a straight line at a given point
- Radical axis and its property
- Common chord
- Condition for orthogonal intersection
- Common tangent equation
- Length of intercept made by a circle on a line
- Angle between two circles
- Basing on director circle of a circle
- Equation of a chord of midpoint is given