PrepZii

mixed

Standard Parabola Geometry

The source defines the standard parabola and its vertex, focus, directrix, axis, and latus rectum.

y^2=4ax

\text{vertex}=(0,0)

\text{focus}=(a,0)

\text{directrix}:x+a=0

\text{axis}:y=0

\text{latus rectum}=4a

L(a,2a),\quad L'(a,-2a)

$a$

parameter or semi-major axis depending on context