This image was acquired from
wikimedia. It was marked as Public Domain or CC0 and is free to use. To verify, go to the source and check the information there.
Keywords from Image Description:
Ellipse Properties of Directrix.svg ellipse including The constant of proportionality is the eccentricity called the directrix The ratios PF are always constant The eccentricity is always between and At zero the ellispe becomes circle at the ellipse becomes parabola Greater than one it is hyperbola Other related images px px