Search results
Results From The WOW.Com Content Network
In geometry, a disk (also spelled disc) [1] is the region in a plane bounded by a circle. A disk is said to be closed if it contains the circle that constitutes its boundary, and open if it does not. [2] For a radius, , an open disk is usually denoted as and a closed disk is ¯.
An open Euclidean unit disk. In mathematics, the open unit disk (or disc) around P (where P is a given point in the plane), is the set of points whose distance from P is less than 1: = {: | | <}. The closed unit disk around P is the set of points whose distance from P is less than or equal to one:
Open disc can refer to: a disk (mathematics) which does not include the circle forming its boundary; the OpenDisc software project This page was last edited on ...
In mathematics, specifically in functional and complex analysis, the disk algebra A(D) (also spelled disc algebra) is the set of holomorphic functions. ƒ : D → , (where D is the open unit disk in the complex plane) that extend to a continuous function on the closure of D.
In mathematics, the uniformization theorem states that every simply connected Riemann surface is conformally equivalent to one of three Riemann surfaces: the open unit disk, the complex plane, or the Riemann sphere.
The open unit disk (the set of all complex numbers of absolute value less than one) is equivalent by a conformal mapping to (see "Poincaré metric"), meaning that it is usually possible to pass between and .
Every topological space X is an open dense subspace of a compact space having at most one point more than X, by the Alexandroff one-point compactification. By the same construction, every locally compact Hausdorff space X is an open dense subspace of a compact Hausdorff space having at most one point more than X.
The small disc around is an open set . In topology and related areas of mathematics, a neighbourhood (or neighborhood) is one of the basic concepts in a topological space. It is closely related to the concepts of open set and interior.