The Parabola 

Introduction:The parabola is a wellknown conic section, formed by slicing a cone with a plane that is parallel to one of the cone's edges. Definition:Geometrically, the parabola is defined by two objects: a point (called the focus) and a line (called the directrix). The parabola is the set of all points at an equal distance from the point and the line (dropping a perpendicular). In the parameterization above, the focus is at (0, a) and the directrix is the line y = a. Properties:
