Viewing topic: Directrix

See sub-topics for Directrix ... >> Mathematics >> Precalculus >> Directrix

Highest Rated Sign

No video has been submitted for this term

Nobody has posted a sign yet.


  • Definition: The directrix of a conic section is the line which, together with the point known as the focus, serves to define a conic section as the locus of points whose distance from the focus is proportional to the horizontal distance from the directrix, with r being the constant of proportionality. If the ratio r=1, the conic is a parabola, if r<1, it is an ellipse, and if r>1, it is a hyperbola (Hilbert and Cohn-Vossen 1999, p. 27).


  • Listed under: Precalculus, Multivariable Calculus

  • There are no comments for this topic.