Focus Definition (Illustrated Mathematics Dictionary) - Math Is Fun

Math is Fun ABCDEFGHIJKLMNOPQRSTUVWXYZ Definition of Focus more ... Focus

A point that helps define an ellipse, parabola or hyperbola.

On the right we see the focus of a parabola:

An ellipse (and a hyperbola) has two focus points, here they are labeled F and G on an ellipse ... have a play:

../geometry/images/geom-ellipse.js?mode=foci See: Parabola, Conic Section, Ellipse Ellipse Copyright © 2025 Rod Pierce

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