Famous Question - Badge - Mathematics Stack Exchange

Famous Question

Question with 10,000 views. This badge can be awarded multiple times.

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Domain of arctan(1/x)

Awarded 14 hours ago

TheEconomist

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Prove or disprove that if A, B, and C are nonempty sets and $A \times B = A \times C$, then $B=C$

Awarded 19 hours ago

Elliott de Launay

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Why is/isn't the derivative of a differentiable function continuous?

Awarded 23 hours ago

Jana

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If $A$ and $B$ are symmetric matrices, so is $A+B$

Awarded yesterday

Maxime Ellehooq de Montbron

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How can I prove that (p→q)∧(p→r) ⇔ p→(q∧r)

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daniel hs

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How is exponentiation defined in Peano arithmetic?

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UQT

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Computing Fourier transform of power law

Awarded Nov 27 at 6:28

knzhou

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Fubini's Theorem for Infinite series

Awarded Nov 26 at 20:38

Jose Antonio

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What am I proving with the Havel-Hakimi theorem?

Awarded Nov 26 at 17:02

Siyah

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prove change of basis matrix is unitary

Awarded Nov 26 at 15:12

i_a_n

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What is the Adjoint of inverse of a matrix?

Awarded Nov 26 at 13:53

Koushik Sahu

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Solve $x^3 +3x -4 =0$ in Real numbers

Awarded Nov 26 at 5:20

titansarus

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Cardinality of all cardinalities

Awarded Nov 25 at 23:02

kennytm

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Can the curl operator be generalized to non-3D?

Awarded Nov 25 at 15:01

Tobias Kienzler

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Continuous Poisson Distribution

Awarded Nov 25 at 8:45

Кирилл Волков

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Show that $\frac{y}{x^2+y^2} $ is harmonic except at $y=0,x=0$

Awarded Nov 24 at 16:44

Tiger Blood

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Market Making Card Game Strategy

Awarded Nov 24 at 11:40

Krish

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Integral of Thomae's function

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MT_

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What is the kernel of the tensor product of two maps?

Awarded Nov 23 at 10:19

Lao-tzu

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How do I evaluate the Lebesgue measure of a ball?

Awarded Nov 23 at 9:14

Number 9

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Quickest way to determine a polynomial with positive integer coefficients

Awarded Nov 23 at 3:28

gt6989b

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Representations of the symmetric group $S_3$

Awarded Nov 22 at 23:47

sky90

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Tensor product of localization is isomorphic to localization of tensor product

Awarded Nov 22 at 14:39

Student

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Asymptotic for binomial coefficients

Awarded Nov 22 at 11:13

VikaV

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Best textbook for Geometric Measure Theory [closed]

Awarded Nov 21 at 16:54

Trajan

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Number of Bit Strings with Five Zeros

Awarded Nov 21 at 7:15

muqsitnawaz

3473 gold badges4 silver badges11 bronze badges

Is composition of covering maps covering map? [duplicate]

Awarded Nov 20 at 18:36

mendes

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Aggregating standard deviation to a summary point

Awarded Nov 20 at 11:00

Dave Clarke

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Angle bracket and sharp bracket for discontinuous processes

Awarded Nov 20 at 9:43

Alfie

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What is the connection between Jordan Canonical Form and minimal polynomial?

Awarded Nov 19 at 19:49

learning_math

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Which perfect squares can be written as the sum of two squares?

Awarded Nov 19 at 2:28

Syed Shibli

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thoughts about $f(f(x))=e^x$

Awarded Nov 18 at 16:47

uforoboa

7,3344 gold badges28 silver badges32 bronze badges

Motivation for spectral graph theory.

Awarded Nov 18 at 9:50

Alexander Gruber♦

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Fourier transform of a radial function

Awarded Nov 18 at 4:14

anonymous

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Truth or lie? "At least one [of the two] of us is a liar."

Awarded Nov 17 at 19:58

Attaque

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Permutation with Duplicates

Awarded Nov 17 at 18:17

Don Wakefield

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Jensen's inequality proof explanation

Awarded Nov 17 at 10:56

Basem Fouda

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Equation of a great circle passing through two points

Awarded Nov 16 at 20:47

Hex4869

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Given the volume of a grain silo and the height of the cylinder of the silo, solve for the radius.

Awarded Nov 16 at 17:33

ecvolm

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What is the difference between partial order relations and equivalence relations?

Awarded Nov 16 at 10:42

SAR

3073 gold badges6 silver badges16 bronze badges

Sylvester's criteria and Negative definite Matrices.

Awarded Nov 16 at 1:48

cmi

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If $f: \Bbb{N} \to \Bbb{N}$ is strictly increasing and $f(f(n))=3n$, find $f(2001)$. [duplicate]

Awarded Nov 16 at 0:46

Bhaskar Vashishth

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Connection between Legendre polynomial and Bessel function

Awarded Nov 15 at 18:03

Fabian

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Expectation of sample variance

Awarded Nov 15 at 10:47

Nascimento de Cos

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A rearrangement of an absolutely convergent series converges absolutely to the same limit

Awarded Nov 14 at 5:56

user125104

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What is the most cited mathematical paper?

Awarded Nov 13 at 20:27

Mizar

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Codomain of a function

Awarded Nov 13 at 16:26

Jonathan.

1,5656 gold badges27 silver badges40 bronze badges

differentiate with respect to a function

Awarded Nov 13 at 15:28

Badshah

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Why is the geometric multiplicity of an eigen value equal to number of jordan blocks corresponding to it?

Awarded Nov 13 at 14:18

MathMan

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What is the most elementary proof that $\lim_{n \to \infty} (1+1/n)^n$ exists?

Awarded Nov 12 at 22:20

marty cohen

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Betting on the appearance of HHT or HTH in a series of coin flips

Awarded Nov 12 at 6:06

Chaim

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Proofs of Sylow theorems

Awarded Nov 11 at 18:31

Karolis Juodelė

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What exactly is an improper subset?

Awarded Nov 11 at 11:26

Raknos13

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Riemann Integrable implies Lebesgue Integrable

Awarded Nov 10 at 18:12

SAS

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Proving that a doubly-periodic entire function $f$ is constant.

Awarded Nov 10 at 18:12

Ivo Terek

80.8k15 gold badges113 silver badges248 bronze badges

Understanding the difference between group representations and modules

Awarded Nov 10 at 14:17

Theorem

8,45913 gold badges60 silver badges101 bronze badges

Homeomorphism between punctured plane and cylinder [duplicate]

Awarded Nov 10 at 3:27

user7090

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Why does Fixed Point Iteration work?

Awarded Nov 9 at 22:08

so.very.tired

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What are some open research problems in Stochastic Processes?

Awarded Nov 9 at 1:17

BrownianMan

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For every infinite $S$, $|S|=|S\times S|$ implies the Axiom of choice

Awarded Nov 8 at 17:58

mathabc

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