Definition:Radius of Complex Disk

Definition

Let $\map B {a, R}$ be the open (complex) disk $\set {z \in \C: \cmod {z - a} < R}$.

Let $\map {\overline B} {a, R}$ be the closed (complex) disk $\set {z \in \C: \cmod {z - a} \le R}$.

In either case, the parameter $R$ is referred to as the radius of $\map B {a, R}$ or $\map {\overline B} {a, R}$.

Also see

• Definition:Center of Complex Disk

• Results about complex disks can be found here.