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2006 IMS
4
4
Part of
2006 IMS
Problems
(1)
Countable
Source: IMS 2006
7/12/2006
Assume that
X
X
X
is a seperable metric space. Prove that if
f
:
X
⟶
R
f: X\longrightarrow\mathbb R
f
:
X
⟶
R
is a function that
lim
x
→
a
f
(
x
)
\lim_{x\rightarrow a}f(x)
lim
x
→
a
f
(
x
)
exists for each
a
∈
R
a\in\mathbb R
a
∈
R
. Prove that set of points in which
f
f
f
is not continuous is countable.
function
limit
topology
advanced fields
advanced fields unsolved