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Good Question

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What are some unsolved problems in group theory which can be explained to a beginner?

Awarded May 21 at 11:03

Robin

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Every finite extension of a finite field is separable

Awarded May 20 at 23:41

user42912

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Intuition for the prime number theorem

Awarded May 17 at 1:08

MathematicsStudent1122

Is there a general formula for the derivative of $\exp(A(x))$ when $A(x)$ is a matrix?

Awarded May 15 at 12:41

Tobias Kienzler

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Bounds on roots of polynomials

Awarded May 15 at 5:41

Mike Jones

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Inverse of a $2 \times 2$ block matrix

Awarded May 12 at 15:18

Claire

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How much Category theory one must learn?

Awarded May 11 at 10:51

user90041

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Decomposing an Affine transformation

Awarded May 10 at 18:38

bigTree

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Is there a "true" value of BB(745)?

Awarded May 9 at 13:52

David Lui

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About the inequality $\sum \frac{x_j}{1-x_j} \sum \frac{y_j}{1-y_j} \ge \sum \frac{x_j}{1-y_j} \sum \frac{y_j}{1-x_j}$

Awarded May 8 at 23:37

Martin R

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Come up with some fun "equation Limericks"

Awarded May 8 at 6:17

Matthew

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In Search Of Elementary Proof Of Kobayashi's Theorem

Awarded May 7 at 14:41

James Moriarty

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Groups with given automorphism groups

Awarded May 6 at 15:05

jpvee

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What is the essence of the new proof of Pythagoras' theorem by the highschoolers Johnson and Jackson?

Awarded May 6 at 15:05

coproc

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If $\lim_n f_n(x_n)=f(x)$ for every $x_n \to x$ then $f_n \to f$ uniformly on $[0,1]$?

Awarded May 6 at 12:49

Romeo

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Numerically stable algorithm for solving the quadratic equation when $a$ is very small or $0$

Awarded May 5 at 16:50

coproc

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coincidental (?) patterns in logs of repeating decimals, e.g. $\ln(2/3)$ vs. $\ln(0.6666666)$

Awarded May 5 at 13:05

Steve Summit

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Double dot product vs double inner product

Awarded May 5 at 0:10

Nick

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Find all primes $p$ such that $(2^{p-1}-1)/p$ is a perfect square

Awarded May 4 at 19:33

Aang

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Without Feynman’s technique, can we evaluate $\int_0^{\infty} \int_0^{\infty} \frac{\ln \left(1+2^x+2^y\right)}{2^{x+y}\left(2^x+2^y\right)}dxdy$?

Awarded May 4 at 5:39

Lai

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Can a free complete lattice on three generators exist in $\mathsf{NFU}$?

Awarded May 3 at 13:11

Noah Schweber

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What is the smallest prime of the form $n^n+8$?

Awarded May 1 at 15:18

Peter

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What's so special about the 4 fundamental subspaces?

Awarded Apr 30 at 17:06

Self_Learner

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What is the difference between a tensor product and an outer product?

Awarded Apr 30 at 13:11

Hermitian_hermit

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Is the radical of a homogeneous ideal of a graded ring homogeneous?

Awarded Apr 30 at 10:08

Makoto Kato

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Convergence of the sequence $\frac{1}{n\sin(n)}$

Awarded Apr 30 at 2:41

Dongyu Wu

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Good book about differential forms

Awarded Apr 27 at 14:35

Mitch

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Does "either" make an exclusive "or"?

Awarded Apr 27 at 8:20

Jonathan Hebert

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Enumerating all fractions by $x \mapsto x +1$ and $x \mapsto-\frac1x$.

Awarded Apr 25 at 11:23

Peter Kagey

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Does the quotient manifold inherit the Riemannian structure?

Awarded Apr 25 at 2:10

BGA

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Does the set of matrix commutators form a subspace?

Awarded Apr 24 at 18:55

EuYu

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Is $z=e^{\frac{1}{\log(x)}}$ a solution to an algebraic equation?

Awarded Apr 24 at 9:26

J. Zimmerman

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How many continuous maps commute with $1 - |2x - 1|$ on $[0, 1]$?

Awarded Apr 22 at 13:31

Keith J. Bauer

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Where does the gap come from? [duplicate]

Awarded Apr 22 at 8:42

Leonardo

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Calculating logs and fractional exponents by hand

Awarded Apr 22 at 2:38

user929304

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Intuition for separable spaces?

Awarded Apr 22 at 0:46

csss

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Complement of maximal multiplicative set is a prime ideal

Awarded Apr 21 at 23:38

4math

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How to imagine "tensoring with Serre's twisted sheaf"

Awarded Apr 20 at 21:27

Adiji

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What are the properties of eigenvalues of permutation matrices?

Awarded Apr 20 at 16:33

Salvador Dali

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What is the implication of Perron Frobenius Theorem?

Awarded Apr 20 at 0:46

Fraïssé

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What explains this peak probability "gain" in the birthday problem?

Awarded Apr 19 at 20:36

Randall

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Measurability with respect to equivalent sub-$\sigma$-algebras for mappings into countably generated spaces

Awarded Apr 18 at 21:07

Julian Newman

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Sum of closed and compact set in a TVS

Awarded Apr 18 at 8:27

ScroogeMcDuck

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Roadmap for learning Topological Data Analysis?

Awarded Apr 17 at 12:33

aevn

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Why are Noetherian Rings important?

Awarded Apr 17 at 8:32

user114442

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Are there non-zero real numbers equal to their "average decimal digit"?

Awarded Apr 16 at 20:45

Robin

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Is there a book only about epsilon delta proofs?

Awarded Apr 16 at 19:46

Poperton

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Difference between a function and a graph of a function?

Awarded Apr 16 at 19:46

user86116

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Does taking countably-many "greedy" closed-ball bites from an open subset of "ice cream" in Euclidean space always leave a set of measure zero?

Awarded Apr 15 at 19:22

bb-poltergeist

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The eigenvalues of a block matrix of the form $\pmatrix{B&C\\0&D}$

Awarded Apr 15 at 10:25

Scorpio19891119

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An open subset of an irreducible set is dense.

Awarded Apr 14 at 14:16

user42912

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What is the difference between square of sum and sum of square?

Awarded Apr 8 at 16:59

achmed

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Solve the differential equation $f'=f/(f\circ f)$

Awarded Apr 4 at 21:03

Antoine du Fresne

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Difference of mapsto and right arrow

Awarded Apr 4 at 2:04

triomphe

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Picard group of product of spaces

Awarded Apr 3 at 4:25

Li Yutong

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Finite-Dimensional Homogeneous Contractible Spaces

Awarded Apr 2 at 16:35

John Samples

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Hyperreal measure?

Awarded Apr 2 at 11:55

Popopo

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Compactness of the Grassmannian

Awarded Apr 1 at 20:54

Tom Jonathan

1,35110 silver badges18 bronze badges

Proving that $\mathbb R^3$ cannot be made into a real division algebra (and that extending complex multiplication would not work)

Awarded Apr 1 at 6:14

learner

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p-adic numbers vs real numbers

Awarded Mar 31 at 15:20

Bourama Toni

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