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Interesting 11 Bountied Hot Week Month

0 votes

2 answers

99 views

Is there any similar equation for π that someone has figured out?

Yajat Shamji's user avatar

572

modified 5 mins ago

0 votes

0 answers

9 views

How should I find the general solution of the partial differential equation $u_{xx}+4u_{yy}=0$ and what's the correct answer to this given PDE?

partial-differential-equations

Enigma's user avatar

59

asked 13 mins ago

2 votes

1 answer

57 views

Winnability of an urn-ball game with restricted two-urn moves

mihaild's user avatar

18k

modified 13 mins ago

0 votes

0 answers

9 views

Integer sequence with largest prime factor

Cristian Baeza's user avatar

943

asked 24 mins ago

0 votes

0 answers

8 views

Product of poset games

combinatorial-game-theory

Yester's user avatar

414

asked 31 mins ago

4 votes

1 answer

2k views

Volume form for a product manifold.

Luke's user avatar

Luke

103

modified 33 mins ago

0 votes

1 answer

767 views

Is there a particular order to doing reflections when there is an inverse reflection (about the line y=x) involved?

Community's user avatar

1

modified 33 mins ago

0 votes

2 answers

28 views

Sequences of Independent Probabilities Intuition

lulu's user avatar

lulu

77.5k

answered 39 mins ago

0 votes

0 answers

16 views

Finding zeros of the product of two analytic functions

katea16's user avatar

21

asked 40 mins ago

3 votes

4 answers

170 views

Evaluate $\int_0^{\frac\pi2} \frac{1}{a \sin ^2x+b \cos ^2x} ,円 \mathrm dx$

Dan's user avatar

Dan

19.2k

answered 45 mins ago

3 votes

3 answers

181 views

High School Geometry Problem involving Golden Ratio

Edward Porcella's user avatar

Edward Porcella

5,451

answered 47 mins ago

4 votes

0 answers

184 views

+50

Is the Collatz map algorithmically decidable?

nonuser's user avatar

672

modified 49 mins ago

1 vote

2 answers

188 views

Find all functions $f : \mathbb R \to \mathbb R$ such that: $f (x f ( y ))+y f ( x) = x f ( y ) + f ( xy ),$ $\forall\ x , y \in \mathbb{R}$

JC Q's user avatar

JC Q

1,782

modified 1 hour ago

1 vote

2 answers

55 views

The $p$-adic valuations of the pairwise differences for all distinct pairs of roots of an irreducible polynomial

Lubin's user avatar

65.7k

answered 1 hour ago

2 votes

0 answers

89 views

Prove or disprove that $a+b+c \geq ab+bc+ca,ドル for positive $a,ドル $b,ドル $c$ satisfying $\sum_{cyc}\frac{1}{a+b+1}\geq1$

Blue's user avatar

Blue

85.2k

modified 1 hour ago

4 votes

1 answer

235 views

+50

Formula for the number of divisors of an integer

Yajat Shamji's user avatar

572

modified 1 hour ago

0 votes

0 answers

18 views

About Riesz representation Theorem for Lp spaces

gabyy_rx's user avatar

1

modified 1 hour ago

2 votes

1 answer

3k views

Explanations about the volume of a regular simplex

Community's user avatar

1

modified 1 hour ago

1 vote

0 answers

64 views

+100

What makes the category of isocrystals over non-algebraically closed field non-semisimple?

François Gatine's user avatar

François Gatine

3,027

modified 1 hour ago

0 votes

0 answers

19 views

How to extend series coefficient for negative coefficients?

calculus

John C's user avatar

117

modified 1 hour ago

0 votes

1 answer

53 views

Why do we find the arc length when given an angle in degrees the way we do?

circles

Robert Israel's user avatar

473k

answered 2 hours ago

0 votes

0 answers

16 views

Hankel Contour: Are Residues Counted or Excluded?

ftel's user avatar

ftel

1

asked 2 hours ago

14 votes

1 answer

810 views

zeros/poles of Laplace transforms of Dirac combs (Riemann zeta function)

Community's user avatar

1

modified 2 hours ago

3 votes

1 answer

69 views

Martingales convergence a.s.

van der Wolf's user avatar

6,223

answered 2 hours ago

0 votes

2 answers

122 views

Use Laplace transforms to solve the integral equation.

RobPratt's user avatar

52.3k

modified 2 hours ago

2 votes

2 answers

61 views

Why is $W_2(\hat{A})$ derived $I$-complete?

coconuthead's user avatar

169

answered 2 hours ago

0 votes

1 answer

45 views

If 2 recursion relation has the same coeficients are the solution proportional?

Simone Coppola's user avatar

159

answered 2 hours ago

1 vote

1 answer

70 views

The set of positive $(x,y,z)$ such that $x^{n_1}+y^{n_2}=z^{n_3}$ for positive integers $n_i$ is dense in the set $[1,\infty)^3$

hbghlyj's user avatar

6,019

modified 3 hours ago

0 votes

0 answers

13 views

Doob's maximal inequality proof

stochastic-analysis

mikasa's user avatar

367

asked 3 hours ago

1 vote

1 answer

57 views

Resultant bounded by norms

DonTelmare's user avatar

1

answered 3 hours ago

2 votes

1 answer

779 views

A game with coin toss

game-theory

David G. Stork's user avatar

30.6k

modified 3 hours ago

1 vote

0 answers

180 views

Null and Range Projections

Lourenco Entrudo's user avatar

Lourenco Entrudo

2,354

modified 3 hours ago

4 votes

2 answers

2k views

Show that the Levy distance is a metric

Bruno Andrades's user avatar

5,334

answered 3 hours ago

-1 votes

0 answers

134 views

How many independent branches proofs of Euler's formula are there?

complex-numbers

Kenay5 55's user avatar

11

modified 4 hours ago

3 votes

0 answers

173 views

Name of the algebraic structure

Avel Bulatov's user avatar

51

modified 4 hours ago

2 votes

1 answer

47 views

Representations of a separable Hilbert space as a Banach lattice

Tomasz Kania's user avatar

17.1k

answered 4 hours ago

0 votes

4 answers

166 views

if $f$ is holomorphic and $f(z)=f(\overline{z})$ then $f$ is constant

complex-analysis

Stardust's user avatar

630

answered 5 hours ago

1 vote

0 answers

52 views

Help: Proof of Ptolemy's Inequality with Complex Numbers

mkcW's user avatar

mkcW

11

asked 5 hours ago

4 votes

1 answer

144 views

if $x^2+1$ is a powerful number then $x=682$?

Bill Dubuque's user avatar

285k

modified 5 hours ago

6 votes

0 answers

54 views

Does the polylogarithm $\mathrm{Li}_k(x)$ solve a first or second order ODE/ADE?

Eli Bartlett's user avatar

2,456

modified 5 hours ago

1 vote

2 answers

1k views

Prove $(p-2)! \equiv 1\pmod p\ $ (equivalent to Wilson's Theorem).

Bill Dubuque's user avatar

285k

modified 5 hours ago

4 votes

1 answer

775 views

Mean value of the rotation angle is 126.5°

Community's user avatar

1

modified 5 hours ago

2 votes

1 answer

78 views

Showing $\sum\limits_{i,j=1}^{n} t^{-a_ia_j} \geq \sum\limits_{i,j=1}^{n} t^{a_ia_j},ドル for $t\in(0,1)$ and $a_i\in(-1,1)$

inequality

Martin R's user avatar

133k

modified 5 hours ago

0 votes

2 answers

37 views

Find the length of the side DQ

Atharv Rege's user avatar

1

modified 6 hours ago

2 votes

0 answers

647 views

Does ternary operations have associative property?

binary-operations

MaoWao's user avatar

16.6k

modified 6 hours ago

2 votes

1 answer

430 views

Conditional expectation on the space of bounded linear operators

MaoWao's user avatar

16.6k

answered 6 hours ago

5 votes

1 answer

4k views

Fourier transform of $\frac{1}{r}$ (Coulomb potential)

Community's user avatar

1

modified 6 hours ago

1 vote

0 answers

47 views

Algebra structure on Haagerup Tensor Product of Operator Spaces

MaoWao's user avatar

16.6k

modified 6 hours ago

0 votes

2 answers

50 views

Perpendiculars passing through diagonal intersection in a quadrilateral formed within a square

jjagmath's user avatar

24.6k

answered 6 hours ago

2 votes

1 answer

155 views

tensor product of $C^*$-algebras.

MaoWao's user avatar

16.6k

answered 6 hours ago

0 votes

0 answers

40 views

Solutions of a non-linear system

byk7's user avatar

byk7

937

asked 7 hours ago

2 votes

1 answer

60 views

Convergence of certain sequence in a $C^*$ algebra

MaoWao's user avatar

16.6k

answered 7 hours ago

0 votes

0 answers

71 views

Is there still active research in the mathematical theory of distributions?

J. W. Tanner's user avatar

64.5k

modified 7 hours ago

10 votes

5 answers

1k views

Why Is the Dual Basis Mathematically Unavoidable?

Man-I-Fold's user avatar

171

modified 7 hours ago

0 votes

1 answer

772 views

Equation of a bounded plane in 3D

Community's user avatar

1

modified 7 hours ago

24 votes

6 answers

1k views

Why is this angle always less than 49ドル°$?

dfnu's user avatar

dfnu

8,388

modified 7 hours ago

1 vote

0 answers

33 views

Scheme over base field $k$ which is algebraically (resp. separably) closed in ring of regular functions of $X$

user267839's user avatar

10k

modified 7 hours ago

8 votes

1 answer

309 views

$\frac{G_1\times G_2}{N_1\times N_2}\cong \bigg(\frac{G_1}{N_1}\bigg)\times \bigg(\frac{G_2}{N_2}\bigg)$

anonymousclassjava's user avatar

anonymousclassjava

87

modified 7 hours ago

0 votes

0 answers

15 views

Proving the solution of heat equation is $C^2_1(\mathcal R^n \times (0,\infty))$

HIH's user avatar

HIH

663

modified 7 hours ago

1 vote

0 answers

37 views

When does $\int_0^{1/2} f(x) \ dx= \int_0^1 f(\varphi(x)),円v(x) \ dx$ hold for $\varphi(t)=\min\{t,1-t\}$?

pedrostrujillo's user avatar

11

modified 8 hours ago

0 votes

2 answers

60 views

Absolute convergence and rearrangements

Paul Frost's user avatar

92.1k

answered 8 hours ago

4 votes

1 answer

187 views

Prove that $\int_0^1\operatorname{Li}_2\left(\frac{1-x^2}{4}\right)\frac{2}{3+x^2},円\mathrm dx= \frac{\pi^3 \sqrt{3}}{486}$

Sangchul Lee's user avatar

185k

modified 8 hours ago

1 vote

1 answer

54 views

Description of the ideals of $A[X]$ using stationary chains of ideals of $A$

Aniruda Suswaram's user avatar

Aniruda Suswaram

395

modified 8 hours ago

0 votes

1 answer

822 views

A problem on triangle and its perpendicular bisectors.

Community's user avatar

1

modified 8 hours ago

2 votes

1 answer

129 views

Why does the Generalized Collatz map (3ドルn+k$) with $k=3^x+2^x$ produce 1,023 cycles at $x=15,ドル but collapse to 1 cycle for $x \ge 21$?

MathPatterns's user avatar

41

answered 8 hours ago

3 votes

3 answers

173 views

Find all real solutions $(x_1,\dots,x_n)\in\mathbb{R}^n$.

systems-of-equations

Ataulfo's user avatar

33.7k

answered 9 hours ago

0 votes

2 answers

121 views

Let $P(x) \in [1,2][x]$ and $P(x) = Q(x)R(x),ドル where $Q(x)$ and $R(x)$ are nonconstant, and $Q(x)$ is monic. Prove: $|Q(3)| > 1$

Amelia Tearheart's user avatar

Amelia Tearheart

151

modified 9 hours ago

2 votes

1 answer

54 views

$f(0)=1, f(x) \ge 0 \ge f'(x), f''(x)\le f(x)$ for $x\ge 0$

T_T's user avatar

T_T

3,338

modified 9 hours ago

0 votes

1 answer

774 views

Are they stable or unstable limit cycles?

Community's user avatar

1

modified 9 hours ago

1 vote

1 answer

55 views

Reasoning behind logistic regression

logistic-regression

J.G.'s user avatar

J.G.

119k

modified 9 hours ago

1 vote

1 answer

46 views

Does the tensor $\Phi$ take this form?

Vladimir Lysikov's user avatar

Vladimir Lysikov

5,350

modified 9 hours ago

7 votes

3 answers

473 views

Frullani version of the classic $\log \left( 1 + 2\alpha \cos px + \alpha^2\right)$ integral.

xpaul's user avatar

49.4k

answered 9 hours ago

2 votes

2 answers

770 views

Ergodicity of a sequence of independent blocks

Community's user avatar

1

modified 10 hours ago

5 votes

1 answer

100 views

Center of a finite perfect group

Haran's user avatar

12.9k

answered 11 hours ago

0 votes

0 answers

25 views

Spectral decomposition of the Neumann-Laplacian

Zaza's user avatar

Zaza

1

asked 11 hours ago

0 votes

0 answers

24 views

Why do we need \rho (utilization)<1 in queuing theory?

AngelP's user avatar

1

asked 11 hours ago

3 votes

1 answer

52 views

Range of base $a$ such that $f(x) = a^x - bx + e^2$ has two distinct zeros for all $b > 2e^2$

Bowei Tang's user avatar

4,563

answered 11 hours ago

2 votes

1 answer

79 views

Why is fact that the determinant of this matrix is 0 equivalent to $x'^T Fx=0$

joão cabral's user avatar

31

modified 12 hours ago

0 votes

1 answer

806 views

How to calculate the angle made by 3 coordinates without using cosine rule

geometry

Community's user avatar

1

modified 13 hours ago

2 votes

0 answers

51 views

Every k-fold cover of the real line by intervals can be decomposed into k distinct covers.

Paul Frost's user avatar

92.1k

modified 13 hours ago

6 votes

1 answer

2k views

Question about Proof of Merten's theorem (Cauchy-Product formula)

Firdous Ahmad Mala's user avatar

Firdous Ahmad Mala

3,613

modified 13 hours ago

0 votes

0 answers

60 views

Show that $C_{k+1} = f_1[C_k] \cup f_2[C_k]$ for $k = 0, 1, 2, ...$ by induction.

Chanhyuk Park's user avatar

53

modified 13 hours ago

0 votes

0 answers

13 views

Verifying One-vs-All Precision and Recall calculations from a multi-class confusion matrix

Minesota's user avatar

1

asked 14 hours ago

3 votes

1 answer

122 views

Extension of Uncertainty Relations to a specific potential in Schrödinger Equation

138 Aspen's user avatar

1,317

answered 14 hours ago

12 votes

4 answers

783 views

Closed form solution for $ \int\limits_{0}^{1} x^{x} (1-x)^{1-x} dx $

Dhairya Kumar's user avatar

117

modified 15 hours ago

7 votes

0 answers

381 views

How to evaluate $\int\limits_{0}^{\frac{\pi}{2}}x^3(\sqrt{\tan x}-\sqrt{\cot x}) dx$?

Dhairya Kumar's user avatar

117

modified 15 hours ago

6 votes

0 answers

240 views

Finding a closed form for $\int\limits_{0}^{1} \frac{1}{x} \ln\left(\frac{\ln\left(\frac{1-x}{2}\right)}{\ln\left(\frac{x+1}{2}\right)}\right)\ dx$

Dhairya Kumar's user avatar

117

modified 15 hours ago

1 vote

1 answer

86 views

The Gateaux derivative and the Jacobian

Jared's user avatar

267

modified 16 hours ago

3 votes

2 answers

67 views

PSP and $\mathbb{R}\times\omega_1$ vs $\mathbb{R} \sqcup \omega_1$

spaceisdarkgreen's user avatar

spaceisdarkgreen

69.5k

modified 18 hours ago

2 votes

4 answers

238 views

Finding the angles of a non-equilateral $\triangle ABC$ with centroid $G$ such that $\angle GAB=\angle GCA=30^\circ$

mezzoctane's user avatar

1,503

modified 21 hours ago

2 votes

1 answer

70 views

Counting disjoint $k$-tuples of lines in $\mathbb F_q^n$

E. Z. L.'s user avatar

155

answered 23 hours ago

1 vote

1 answer

356 views

Binet's second log-gamma formula

DroneBetter's user avatar

612

modified yesterday

0 votes

1 answer

76 views

$\mathbb{C}(\lambda x^ay^b,\mu x^cy^d)=\mathbb{C}(x,y)$ if and only if $ad-bc= \pm1$

user237522's user avatar

7,257

modified yesterday

1 vote

0 answers

33 views

Type changing $(1,1)$ to $(2,0)$ tensor

riemannian-geometry

Andrew's user avatar

2,296

asked yesterday

0 votes

0 answers

40 views

How to see $x_1\geq 0$ in the primal implies $p' A_1 \leq c_1$ in the dual, when there are no other constraints than just $x_1\geq 0$?

niobium's user avatar

1,367

modified yesterday

1 vote

1 answer

776 views

Heat equation with different boundary conditions

Community's user avatar

1

modified yesterday

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