30.7 The Parabola and a Unified View of Conic Sections
Point 3 of 6
30.7.3 Focus, Directrix, and Geometric Properties
Core idea
The focus and directrix bracket the curve front and back, and its reflective property funnels every incoming signal to the focus.
Module goal. Introduce the parabola and, through equal point-line distance and eccentricity, thread all three curves into one system, wrapping up the coordinate method.
eastmath.com · 30.7 The Parabola and a Unified View of Conic Sections · 30.7.3 Focus, Directrix, and Geometric Properties