In mathematics, "subtended" usually refers to the direct relationship between an angle and its arc length, or for solid angle the area on a unit sphere cut out by the envelope of the vectors defining the perimeter. For example, according to circle geometry, in a circle equal angles subtend equal arc lengths. The converse is also true, equal arc lengths subtend equal angles. The solid angle subtended by a circular cone of opening angle θ is 2π[1-cos(θ)]. A solid angle is the three dimensional analog of the ordinary angle. ... A solid angle is the three dimensional analog of the ordinary angle. ...

See also

• Central angle