View source for Centre (mathematics)

In [[mathematics]], '''centre''' may refer to:


* In an algebraic structure, elements that commute with every element of the structure
** The [[centre of a group]], elements that commute with every group element
* The centre of a [[circle]]
* The centre of mass, centroid or [[barycentre]] of a geometrical figure
* In [[triangle geometry]]
** The [[centroid]], intersection of the [[median]]s
** The [[circumcentre]], intersection of the [[perpendicular bisector]]s of the sides, centre of the circle through the vertices
** The [[nine-point centre]]
** The [[orthocentre]], intersection of the [[altitude]]s
** The [[incentre]], centre of a circle [[tangent]] to the sides 
** The [[excentre]]s, centres of the three circles internally tangent to one side and  externally to the other two