Math 41 Sections 11.1 and 11.2 - 11.1 Conics - the word...

11.1 Conics
- the word conic derives from the word cone. A cone has a fixed line called an axis , a vertex , generators,
and the two parts(sides) of the cone are called nappes .
- conics , an abbreviation for conic sections , are curves that result from the intersection of a right circular
cone and a plane. Circles are made when a plane is perpendicular to the axis of the cone and intersects
each generator, but intersects only one nappe of the cone; parabolas when the plane is tilted farther so
that it is parallel to one generator and intersects only one nappe of the cone; and hyperbolas when the
plane intersects both nappes.
Degenerate Conics – if the plane does not contain the vertex, it is the intersection of the plane and the
cone is a point, a line, or a pair of intersection lines.
11.2 The Parabola
- a parabola is the collection of all points P in the plane that are the same distance from a fixed point F as
they are from a fixed line D. The point F is called the focus of the parabola, and the line D is its