Revision as of 22:37, 4 February 2019 by Chenr28 (talk | contribs)

This article is a stub. Help us out by expanding it.

The radius of a circle is the distance from the center to any point on the circle. Identical definitions hold for the sphere and hypersphere. The plural form of radius is radii.

The radius of a circle is often denoted using R or r.

[asy]size(150); pair O=origin, P=dir(30); D(unitcircle); D(O--P); MP("O",D(O),NNW); MP("P",D(P),NE); MP("r",midpoint(O--P),NNW);[/asy]

See Also

Invalid username
Login to AoPS