Processing math: 100%
Open ball
Set
context
⟨
d
,
X
⟩
… metric space
context
a
∈
X
definiendum
B
a
:
R
∗
+
→
P
(
X
)
definiendum
B
a
(
r
)
:=
{
x
|
d
(
x
,
a
)
<
r
}
Discussion
Reference
Wikipedia:
Ball (Mathematics)
Parents
Context
Metric