10-04-2017, 09:11 PM
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INTRODUCTION
The parabola is the locus of all points in a plane that are the same distance from a line in the plane, the directrix, as from a fixed point in the plane, the focus.
The parabola has one axis of symmetry, which intersects the parabola at its vertex
The distance from the vertex to the focus is p .
The distance from the directrix to the vertex is also p .