Definition:Exterior Point (Complex Analysis)

Definition

Let $S \subseteq \C$ be a subset of the complex plane.

Let $z_0 \in \C$.

Definition 1

$z_0$ is an exterior point of $S$ if and only if $z_0$ has an $\epsilon$-neighborhood which is disjoint from $S$.

Definition 2

$z_0$ is an exterior point of $S$ if and only if:

$z_0$ is not an interior point of $S$

and:

$z_0$ is not a boundary point of $S$.

Also see

• Equivalence of Definitions of Exterior Point (Complex Analysis)