Mathematics Stack Exchange

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How do I find the largest circle that can be inscribed in the union of 3 other circles (which I'm allowed to move around)?

linear-algebra geometry optimization

asked 3 mins ago Gabi 35

1

vote

0

answers

4

views

Calculate the limit $\lim _{n \rightarrow \infty} \frac{[\ln (n)]^{2}}{n^{\frac{1}{\ln (\ln (n))}}}$.

real-analysis calculus limits

asked 4 mins ago why_me 11

2

votes

1

answer

41

views

Showing that any of n balls drawn without replacement has the same probability of being a particular colour

probability expected-value

modified 5 mins ago Antoni Parellada 5,727

16

votes

1

answer

319

views

Show that $\sum\limits_{n=1}^{\infty}\frac1{n^2}=\sum\limits_{n=1}^{\infty}\frac3{n^2\binom{2n}n}$ without actually evaluating both series

sequences-and-series alternative-proof

modified 5 mins ago mrtaurho 11.3k

6

votes

0

answers

72

views

any method to estimate determinant of a matrix?

linear-algebra matrices determinant

modified 6 mins ago dk1111 61

1

vote

1

answer

15

views

Doubts about the Zorich explanation of coordinate systems and orientation classes

coordinate-systems surfaces orientation

answered 8 mins ago Paul Sinclair 28.1k

0

votes

1

answer

35

views

Relationship between central divisor pairs

elementary-number-theory

answered 9 mins ago Ali Kwant 11

7

votes

0

answers

140

views

Evaluating a Polynomic-Trigonometric-Hyperbolic Integral

integration definite-integrals closed-form

modified 9 mins ago mrtaurho 11.3k

0

votes

0

answers

8

views

Complete solutions to $\mathrm{e}^{\mathrm{i} \alpha_1} + \cdots + \mathrm{e}^{\mathrm{i} \alpha_n} = 0$.

complex-numbers summation roots-of-unity

asked 9 mins ago Goulifet 598

5

votes

3

answers

201

views

On the series expansion of $\frac{\operatorname{Li}_3(-x)}{1+x}$ and its usage

proof-verification power-series polylogarithm cauchy-product polygamma

modified 9 mins ago mrtaurho 11.3k

-1

votes

0

answers

4

views

How to use the Cauchy Integral formula with a point that does not exist in the enclosed curve?

complex-analysis

asked 9 mins ago cba 19

10

votes

1

answer

284

views

A difficult logarithmic integral and its relation to alternating Euler Sums

integration sequences-and-series closed-form harmonic-numbers euler-sums

modified 2 mins ago mrtaurho 11.3k

0

votes

1

answer

13

views

Martingales and Optimal Stopping. Prove: $E[M_T] = E[M_0]$

stochastic-processes martingales

modified 11 mins ago pico 641

1

vote

0

answers

59

views

Brownian motion and the heat equation - diffusion coefficient

probability-distributions stochastic-processes brownian-motion heat-equation laplacian

modified 11 mins ago Denis 91

1

vote

0

answers

16

views

How many way to arrange colored blocks in a cube

combinations

modified 13 mins ago Gary 11

0

votes

0

answers

3

views

Domain and range of n-ary relations.

set-theory relations

asked 18 mins ago Soham Sarkar 119

2

votes

1

answer

18

views

Closed form for $\sum_{k=0}^{\infty}\int_0^1 e^{-(x+kL)^2}dx$

calculus integration power-series

answered 20 mins ago Alex 17.7k

0

votes

1

answer

32

views

Can a nontrivial group have an absorbing element?

abstract-algebra group-theory ring-theory

answered 21 mins ago Shaun 24k

1

vote

1

answer

31

views

The existence of the power set of an infinite set

set-theory cardinals infinity foundations

answered 23 mins ago Doctor Who 2,239

1

vote

3

answers

33

views

How to convert the recursive function $f(n)=n*f(n-1)+1$ to an explicit function

sequences-and-series recursion

answered 26 mins ago D.md 61

0

votes

0

answers

12

views

Using Leibniz’s rule for differentiating under the integral sign for line integrals

complex-analysis

modified 27 mins ago Sebastiano 2,269

0

votes

0

answers

9

views

universal property of Albanese variety

algebraic-geometry

asked 30 mins ago Manoel 1,880

0

votes

0

answers

17

views

What injection $2^\omega\to \omega_1$ can we take?

set-theory

asked 30 mins ago roi_saumon 2,778

3

votes

0

answers

25

views

Heat PDE with unusual, inhomogeneous Neumann boundary condition

partial-differential-equations boundary-value-problem

modified 34 mins ago Gert 271

2

votes

1

answer

40

views

Local behaviour of a module localized at a prime ideal

commutative-algebra localization local-rings

modified 36 mins ago user26857 42k

2

votes

1

answer

33

views

Can we define $z^{\frac{1}{2}}$ as a holomorphic function on $\mathbb{C}\left\backslash \left\{ 0\right\} \right.$?

complex-analysis cauchy-riemann-equations

modified 37 mins ago Hana 85

2

votes

0

answers

12

views

Historical proofs of the series expression for the Bessel function of the first kind

sequences-and-series math-history laurent-series bessel-functions

modified 38 mins ago viiv 21

0

votes

0

answers

5

views

Is standard deviation of residuals of Markov switching GARCH model regime specific?

statistics stochastic-processes finance markov-process

asked 39 mins ago Chp 31

0

votes

0

answers

10

views

Question about Weingarten map / differential of Gauss map

real-analysis differential-geometry surfaces

asked 45 mins ago HannahBloom 77

0

votes

0

answers

8

views

Integration using the Parseval-Plancherel identity

real-analysis integration complex-analysis analysis fourier-analysis

asked 50 mins ago user824530 51

1

vote

1

answer

50

views

Problem with linear transormations, their direct sums and properties

linear-algebra linear-transformations direct-sum

modified 50 mins ago Doctor Who 2,239

1

vote

1

answer

23

views

Finding initial conditions where solutions of $y^{(5)}+y''=\cos t$ are bounded/unbounded.

ordinary-differential-equations initial-value-problems

answered 54 mins ago Andrei 22.7k

-1

votes

0

answers

21

views

How many equal-sized cuboids fits in a larger cuboid

combinatorics solid-geometry

modified 1 hour ago David G. Stork 20.8k

0

votes

0

answers

7

views

Is $P=\{x\in\mathbb{R}_+: n\mapsto\lfloor nx\rfloor\text{ is a p.r.f.}\}$ closed under addition?

computability

asked 1 hour ago metamorphy 17.9k

2

votes

0

answers

19

views

Is there a closed form for $\sum_{n=1}^\infty\frac{2^{2n}H_n}{n^3{2n\choose n}}?$

real-analysis integration sequences-and-series binomial-coefficients harmonic-numbers

modified 1 hour ago Ali Shather 15.5k

0

votes

0

answers

14

views

Hellinger Distance of two mixture multivariate Normal Distributions

statistics

modified 1 hour ago dsmalenb 311

0

votes

1

answer

23

views

What is the difference between $\prod\limits_{i=1}^L \mathbb{R}^{k_i}$ and $\mathbb{R}^{\prod\limits_{i=1}^L k_i} $?

linear-algebra general-topology matrices vector-spaces

answered 1 hour ago Mark 976

1

vote

0

answers

20

views

Why my fourier transform is not working properly?

fourier-analysis python fast-fourier-transform

asked 1 hour ago Armando Canales Lima 11

0

votes

0

answers

9

views

How to define a metric from a measure and a similarity ordering?

measure-theory metric-spaces

asked 1 hour ago Mars 722

0

votes

1

answer

15

views

Partitioning cartesian products of the form $[0,n]\times[0,m]$ ($n,m\in\mathbf{N}$) “diagonally”

combinatorics discrete-mathematics elementary-set-theory set-partition

answered 1 hour ago Air Mike 1,019

1

vote

0

answers

36

views

Quaternion argument formula

complex-numbers quaternions

modified 1 hour ago Robert Lewis 61.6k

0

votes

0

answers

11

views

Cohomology classes $H^{1,1}(M, \mathbb{C})$ on Kaehler manifold

differential-geometry complex-geometry kahler-manifolds de-rham-cohomology

asked 1 hour ago Joe Aaron 710

0

votes

0

answers

5

views

$V$ Vector space, Q Skew Symmetric nondgenerate bilnear operator $\rightarrow$ \rightarrow $det(Q)=1$ and dimension of $V$ is even?

linear-algebra

modified 1 hour ago HaKuNa MaTaTa 4,811

1

vote

0

answers

13

views

Characterization of Connected Locally Connected Sets

general-topology connectedness locally-connected

asked 1 hour ago Ishan Deo 2,756

0

votes

1

answer

11

views

Does first order stationary random process means that all variables in the collection have the same distribution?

stochastic-processes random-variables ergodic-theory stationary-processes

answered 1 hour ago John Deterious 171

0

votes

0

answers

37

views

1D Boundary value problem: Show that larger width implies larger velocity.

partial-differential-equations boundary-value-problem maximum-principle

modified 1 hour ago Scuderi 169

0

votes

2

answers

11

views

Intuitively, what is the general overlap/difference between conformal vs orthogonal transformations, or the terms in general?

calculus differential-geometry differential-forms differential

answered 1 hour ago Vercassivelaunos 2,229

3

votes

0

answers

64

views

Computing $\sum_{n=1}^\infty\frac{2^{2n}H_{n+1}}{(n+1)^2{2n\choose n}}$

real-analysis integration sequences-and-series binomial-coefficients harmonic-numbers

modified 1 hour ago Felix Marin 75.1k

0

votes

0

answers

11

views

on Baker theorem of linear form in logarithm

minimal-polynomials

modified 1 hour ago Abdo 95

2

votes

0

answers

31

views

Integral involving distance to the boundary

integration lebesgue-integral

modified 1 hour ago Isak 61

0

votes

0

answers

19

views

Why is the pushforward of an invertible sheaf on BG to its coarse scheme not invertible?

algebraic-geometry

asked 1 hour ago stupid_question_bot 399

0

votes

0

answers

10

views

About Green's function

partial-differential-equations greens-function

asked 1 hour ago John M-D94 149

0

votes

1

answer

14

views

Integration of Box Function between 0 to 1

integration functions

answered 1 hour ago Isaac Browne 6,430

1

vote

2

answers

59

views

Given $n$, find $2$ positive integers $a,b$ such that $a+b=n$ and $LCM(a,b)$ is as minimum as possible

elementary-number-theory algorithms

modified 1 hour ago fleablood 101k

2

votes

2

answers

41

views

Weak topology of normed space

functional-analysis weak-topology

answered 1 hour ago Jacob Manaker 1,535

2

votes

0

answers

13

views

Show expectation of minimum of the stopped martingale is $-\infty$

probability-theory measure-theory martingales

modified 1 hour ago Landon Carter 10.9k

0

votes

0

answers

7

views

Analyzing revenue and historical data to estimate profit

time-series

asked 1 hour ago Alpha Bing 11

3

votes

1

answer

39

views

Local-global test of algebraicity

number-theory

answered 1 hour ago reuns 42.9k

0

votes

0

answers

25

views

Why does the Arzela-Ascoli theorem assume each $f_n$ is continuous, if equicontinuity implies it anyway?

real-analysis

asked 1 hour ago Jon J 31

0

votes

1

answer

20

views

Countability of the set of $t$ such that $E-tB$ is not injective

functional-analysis compact-operators self-adjoint-operators

answered 1 hour ago Ruy 178

0

votes

1

answer

15

views

Sufficient conditions for directional derivatives of a particular function

multivariable-calculus

modified 1 hour ago K.defaoite 3,056

0

votes

0

answers

17

views

Serie $u_n \underset{ n \to +\infty}{\sim} a^{n^{\mu}}$

real-analysis sequences-and-series

asked 1 hour ago zestiria 29

0

votes

0

answers

15

views

Construction of Weil representation

functional-analysis representation-theory

asked 1 hour ago Siddhartha 601

-1

votes

0

answers

15

views

Continuous Branch of Logarithm

complex-analysis logarithms

asked 1 hour ago asrxiiviii 432

-1

votes

0

answers

6

views

sub-exponential norm of squared gaussian random variable

normal-distribution norm exponential-distribution gaussian

asked 2 hours ago Nicolas H 27

4

votes

1

answer

22

views

Union of all Borel subgroups is the whole group

algebraic-geometry algebraic-groups

answered 2 hours ago Alex Youcis 41.6k

0

votes

0

answers

9

views

Problem with pointing an operator with given properties

matrices functional-analysis

asked 2 hours ago Novice 501

0

votes

0

answers

14

views

Is there a simple solution to this spherical n-dimensional geometry problem arising in probability setting?

probability geometry solid-angle

modified 2 hours ago David G. Stork 20.8k

5

votes

1

answer

47

views

How many four digits numbers are there not containing zero and multiplication of its digits divisible by 7?

discrete-mathematics permutations solution-verification problem-solving

modified 2 hours ago Axel 492

0

votes

0

answers

14

views

Show positiveness for a Cauchy problem

ordinary-differential-equations analysis solution-verification cauchy-problem

asked 2 hours ago andereBen 369

2

votes

1

answer

91

views

+50

Show that an even integer in $\mathbb Z_{2n}$ can be written twice as a sum of disjoint terms of a sequence (EDITED)

number-theory summation pigeonhole-principle

modified 2 hours ago Savio 756

1

vote

0

answers

36

views

Prove that $f(x) = 0$ for some $x$ under the assumption that there exists a continuous function $g$ such that $f + g$ is non decreasing.

real-analysis continuity recreational-mathematics problem-solving

modified 2 hours ago crystal_math 969

0

votes

2

answers

24

views

$\mathbb R$ with the topology generated by $\tau = \{(a, \infty): a \in \mathbb R\}$ is pseudocompact

general-topology continuity compactness

answered 2 hours ago Henno Brandsma 173k

0

votes

0

answers

10

views

Interchange of weak limits without uniform convergence

real-analysis probability probability-theory weak-convergence interchange-of-limits

asked 2 hours ago forgottenarrow 1,126

0

votes

1

answer

22

views

Probability to die in the first or second term?

probability

answered 2 hours ago N. F. Taussig 55.3k

3

votes

1

answer

32

views

Find maximum Gaussian function that fits under a curve

optimization maxima-minima gaussian

answered 2 hours ago K.defaoite 3,056

1

vote

1

answer

12

views

About the Brouwer degree of a mapping between subsets of the real line.

real-analysis functional-analysis analysis differential-geometry differential-topology

answered 2 hours ago Peter Franek 9,366

0

votes

0

answers

12

views

How to solve $x[n]\ast x[n]=u[n]$?

convolution signal-processing z-transform

asked 2 hours ago bertozzijr 843

4

votes

0

answers

26

views

Prove existence of triangle with vertices in $\mathbb{Z}^2$, each angle of which is $\varepsilon$-close to $\pi/3$.

geometry elementary-number-theory euclidean-geometry triangles

modified 2 hours ago Blue 59.5k

0

votes

0

answers

13

views

What is “Expectation over Y” in the Law of Total Expectation

probability expected-value

asked 2 hours ago Catbuilts 101

0

votes

1

answer

15

views

Partition $N$ items into $K$ equally sized partitions while retaining groups in original items

optimization integer-programming

answered 2 hours ago RobPratt 14.2k

0

votes

0

answers

23

views

Construction of reals, Dedekind cuts

real-numbers

asked 2 hours ago Sion 1

2

votes

1

answer

35

views

Refresh on factoring out GCF, specifically involving smallest exponent on all common terms

algebra-precalculus factoring fractions

answered 2 hours ago N. F. Taussig 55.3k

0

votes

0

answers

20

views

Probability of actually being sick after 3 positive tests? (Bayes problem?)

probability bayesian

asked 2 hours ago dd22205 245

2

votes

1

answer

32

views

Understanding the statement and the proof of Bertini's theorem in Griffiths and Harris

complex-analysis algebraic-geometry complex-geometry intersection-theory

answered 3 hours ago Tabes Bridges 1,120

2

votes

0

answers

36

views

Expectation of $\frac{\langle Gx, Gy\rangle}{\|Gx\|_2\|G y\|_2}$ where $\langle x, y\rangle = \rho$

linear-algebra probability geometry random-matrices

modified 3 hours ago Thomas Ahle 3,026

1

vote

1

answer

27

views

Random Walk Probability - Tennis Match

probability random-walk

modified 3 hours ago Parth Lohomi 157

1

vote

0

answers

22

views

Question On Solutions for a Specific Congruence $ax \equiv 1 \pmod p$ when $p$ is prime and $p \not\mid a$

modular-arithmetic congruence-relations

modified 3 hours ago Sil 9,459

0

votes

0

answers

17

views

What is the dual of $l_p$ norms in $\mathbb{C}^n$, where $1 \leq p \leq \infty$?

linear-algebra normed-spaces inner-product-space dual-spaces

modified 3 hours ago Faqir Chand 97

0

votes

2

answers

54

views

How do we create new mathematics symbols/concepts?

soft-question education philosophy

modified 3 hours ago Jean Marie 45.9k

1

vote

2

answers

85

views

Do commuting matrices with real and complex eigenvectors still share eigenvectors?

linear-algebra complex-numbers eigenvalues-eigenvectors quantum-mechanics permutation-matrices

modified 3 hours ago user8675309 2,754

2

votes

0

answers

22

views

What is a good lower-bound for $P(t|a^Tx| \le \|x\|^2)$, where $a$ is a fixed unit vector in $\mathbb R^m$, $x \sim N(0, I_m)$, and $t > 0$?

probability concentration-of-measure distribution-tails

modified 3 hours ago dohmatob 5,687

0

votes

1

answer

27

views

Proof that if the difference of terms of two convergent sequences is null, then the limit of the sequences are equal

real-analysis solution-verification alternative-proof

modified 4 hours ago Brian M. Scott 514k

4

votes

0

answers

52

views

Prime Spectrum of a ring: why is Geometry captured by local rings?

algebraic-geometry commutative-algebra sheaf-theory schemes

modified 4 hours ago KReiser 29.1k

1

vote

0

answers

23

views

Expansion in a non-orthogonal basis in infinite-dimensional space

linear-algebra hilbert-spaces

asked 4 hours ago ZeroTheHero 305

-2

votes

2

answers

66

views

Check pointwise and uniform convergence

analysis uniform-convergence pointwise-convergence

modified 4 hours ago José Carlos Santos 281k

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