CoreConics

Ellipse

x²/a² + y²/b² = 1

Overview

An ellipse is the set of points where the sum of distances to two foci is constant.

Domain

[-a, a]

Range

[-b, b]

Key Properties

1

a = semi-major axis, b = semi-minor axis

2

Foci at (±c, 0) where c² = a² − b²

3

Sum of distances to foci = 2a

4

Circle is a special case (a = b)

Key Insight

Planets orbit in ellipses with the Sun at one focus — Kepler's First Law!

Visualize Ellipse

Interact with the graph and explore this curve in the analytic geometry visualizer.

Open Visualizer