concentric circles

A collectionMathworldPlanetmath of circles is said to be concentric if they have the same center. The region formed between two concentric circles is therefore an annulus.

In the following picture, the gray region is the annulus delimited by the two black concentric circles.

Title concentric circles
Canonical name ConcentricCircles
Date of creation 2013-03-22 12:55:25
Last modified on 2013-03-22 12:55:25
Owner drini (3)
Last modified by drini (3)
Numerical id 5
Author drini (3)
Entry type Definition
Classification msc 03-00
Defines annulus