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Bunbury
  • Member for 4 years, 1 month
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486 votes
10 answers
63k views

Best Sets of Lecture Notes and Articles

  • 48.2k
169 votes
4 answers
61k views

Overview of basic results about images and preimages

159 votes
8 answers
28k views

Intuition of the meaning of homology groups

  • 4,145
134 votes
15 answers
14k views

Are "if" and "iff" interchangeable in definitions?

  • 2,427
93 votes
5 answers
65k views

Difference between gradient and Jacobian

  • 1,157
88 votes
4 answers
36k views

$X$ is Hausdorff if and only if the diagonal of $X\times X$ is closed

  • 1,950
69 votes
11 answers
31k views

Why do we use a Least Squares fit?

  • 3,077
66 votes
2 answers
16k views

Cardinality of Borel sigma algebra

  • 3,186
63 votes
14 answers
20k views

Dot Product Intuition

  • 3,060
61 votes
2 answers
201k views

Is there really no way to integrate $e^{-x^2}$?

  • 1,541
53 votes
2 answers
16k views

Lebesgue measurable but not Borel measurable

  • 13.7k
49 votes
5 answers
14k views

Difference between topology and sigma-algebra axioms.

  • 2,876
48 votes
6 answers
146k views

What is difference between cycle, path and circuit in Graph Theory

44 votes
4 answers
13k views

Interpretation of limsup-liminf of sets

  • 1,921
44 votes
1 answer
26k views

Lebesgue measurable set that is not a Borel measurable set

  • 1,925
44 votes
8 answers
10k views

What is the intuition for the point-set topology definition of continuity?

  • 3,675
41 votes
6 answers
16k views

Examples of uncountable sets with zero Lebesgue measure

  • 16.7k
40 votes
5 answers
4k views

Is there a $\sigma$-algebra on $\mathbb{R}$ strictly between the Borel and Lebesgue algebras?

36 votes
3 answers
19k views

Topologist's sine curve is not path-connected

35 votes
4 answers
14k views

An intuitive idea about fundamental group of $\mathbb{RP}^2$

  • 7,095
30 votes
7 answers
59k views

Are Singleton sets in $\mathbb{R}$ both closed and open?

  • 2,021
28 votes
1 answer
5k views

Constructing a subset not in $\mathcal{B}(\mathbb{R})$ explicitly

  • 68.2k
28 votes
3 answers
54k views

Is there any difference between $P$ and $\Pr$ to represent probabilities?

27 votes
5 answers
21k views

What is the difference between topological and metric spaces?

24 votes
4 answers
41k views

Rigorous proof that $dx dy=r\ dr\ d\theta$

  • 777
22 votes
2 answers
18k views

Is it true that a subset that is closed in a closed subspace of a topological space is closed in the whole space?

18 votes
3 answers
3k views

Why do we need (the abstract concept of) random variables (in discrete probability models)?

  • 1,047
14 votes
2 answers
6k views

Set of points at which sequence of measurable functions converge (another approach)

11 votes
5 answers
16k views

Why do we use dummy variables in integrals?

  • 621
9 votes
3 answers
11k views

Cantor set: Lebesgue measure and uncountability

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