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Is a function of the form $g(t):=\int_{[0,\:t]\times E}f\:{\rm d}(\lambda\otimes\mu)$ continuous or only right-continuous?

real-analysis probability-theory measure-theory

modified 1 min ago 0xbadf00d 12.2k

0

votes

0

answers

4

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The sequence $\{a_n\}_{n=1}^\infty$ defined by $a_1=1$ and $a_{n+1}=1+\frac{1}{a_n}$ is a Cauchy sequence

real-analysis calculus

asked 2 mins ago Steve 1,167

0

votes

0

answers

7

views

Union of a family of pairwise distinct hyperplanes over an infinite field

linear-algebra vector-spaces

modified 3 mins ago GRJ 452

0

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0

answers

4

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Formula(s) and intuition for 3D rotation when vector center is not Origin = (0,0,0)

multivariable-calculus vectors 3d rotations

asked 3 mins ago Ian Ambrose 31

0

votes

0

answers

4

views

Neighborhoods, convergence of quotient topology [0,1] x N

general-topology convergence-divergence quotient-spaces

asked 4 mins ago user917000 3

3

votes

2

answers

36

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Defining derivatives in Real/Complex Analysis?

real-analysis complex-analysis limits functions derivatives

modified 6 mins ago Martin R 78.3k

1

vote

1

answer

14

views

Proof for Kleene star and concatenation

formal-languages automata

modified 6 mins ago Mark Saving 13.8k

2

votes

1

answer

33

views

Is it true that if $g\sim h$, then $\lim_{x\to 0}\frac{f(g(x))}{f(h(x))}=1$?

calculus limits

answered 6 mins ago user10354138 29.7k

2

votes

0

answers

31

views

Inellipse Area Conjecture and Siebeck-Marden Theorem

geometry conic-sections

modified 8 mins ago Vue 675

0

votes

0

answers

15

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Prove $\frac{e^x-1}{e^x+1}=\frac{e^{\frac{x}{2}}-e^{-\frac{x}{2}}}{e^{\frac{x}{2}}-e^{-\frac{x}{2}}}$

trigonometry logarithms exponential-function

asked 8 mins ago gete 1,136

0

votes

0

answers

5

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Arzelà-Ascoli for families of manifolds

analysis differential-geometry reference-request

asked 8 mins ago Augusto Santos 841

0

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0

answers

3

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Integral Domains (invertible elements)

abstract-algebra ring-theory integral-domain

asked 9 mins ago Dmvc 1

1

vote

1

answer

12

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Orthonormal basis in infinite dimensional real vector space

linear-algebra abstract-algebra vector-spaces inner-products

modified 11 mins ago Kavi Rama Murthy 280k

0

votes

1

answer

40

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Solution to a matrix quadratic

linear-algebra matrices matrix-equations quadratic-forms

answered 12 mins ago Petrus1904 501

15

votes

0

answers

242

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Show that there are no real solutions of $1 + \sum_{n = 1}^{\infty} \frac{x^n}{\prod_{k=1}^{n} H_k} = 0$ where $H_k = \sum_{i=1}^{k} \frac{1}{i}.$

real-analysis harmonic-numbers

modified 13 mins ago Vue 675

0

votes

2

answers

31

views

Avg time for human to reach a destination

probability

modified 13 mins ago tommik 27.1k

1

vote

0

answers

10

views

find the class (coset) of a rotation.

group-theory

modified 13 mins ago John Infinity 2,464

1

vote

0

answers

8

views

A Question About (6.15) in Deep Learning (Goodfellow et al.)

probability-distributions optimization norm expected-value inner-products

asked 13 mins ago Wei-Cheng Liu 564

-1

votes

1

answer

26

views

Solving system of differential equations of 2nd order

calculus ordinary-differential-equations

answered 18 mins ago Vasile 329

-1

votes

1

answer

23

views

Given that $a_n$ and $b_n$ are non-negative sequences such that $a_n\ge b_n$ and $a_n\to 0$, does that mean $b_n\to 0$?

sequences-and-series limits inequality convergence-divergence

answered 18 mins ago Angel 158

0

votes

0

answers

15

views

definition of stirling numbers

combinatorics stirling-numbers

modified 23 mins ago user1062 325

-2

votes

0

answers

11

views

Its about principle of excluded middle and First order Logic

first-order-logic predicate-logic

modified 23 mins ago Wnnabitzy 1

0

votes

1

answer

22

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The limit of a complex function becoming the limit of 0 (algebraically inside the limit)

complex-analysis limits analysis complex-numbers absolute-value

modified 25 mins ago David C. Ullrich 81.7k

11

votes

0

answers

88

views

+200

Existence of orthonormal basis for $L^2(G)$ in $C_c(G)$.

operator-theory hilbert-spaces harmonic-analysis orthonormal locally-compact-groups

modified 27 mins ago Calculix 2,672

1

vote

0

answers

9

views

Borel sigma algebra on the unit sphere

measure-theory compactness banach-spaces borel-sets

asked 30 mins ago Zlyp 11

-2

votes

0

answers

15

views

(internal) product of cyclic subgroups or generated subgroups in general: $\langle x \rangle$ $\langle y \rangle$ = $\langle x,y \rangle$?

abstract-algebra group-theory

modified 35 mins ago John Smith Kyon 551

0

votes

1

answer

14

views

How can I define a function, which maps from a set to a partition of the other set?

functions elementary-set-theory

answered 36 mins ago Dan Rust 27.9k

1

vote

0

answers

5

views

how can I calculate Heteroscedastic data like below equation

probability statistics

asked 36 mins ago Mohammed 11

1

vote

0

answers

18

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The relation between Poincaré linearization theorem and stable manifold theorem.

differential-geometry dynamical-systems coordinate-systems

modified 37 mins ago Charlie Chang 1,225

69

votes

14

answers

31k

views

What isn't a vector space?

vector-spaces

answered 40 mins ago koralgooll 253

3

votes

1

answer

41

views

Doubt on a method used in an article ( extreme value problem of trig function)

trigonometry polynomials optimization maxima-minima extreme-value-theorem

modified 42 mins ago Dotman 121

0

votes

0

answers

3

views

How to interpret negative adjusted r-squared and significant coefficients in fixed effect model?

regression data-analysis

asked 45 mins ago Kacper 1

0

votes

0

answers

4

views

A question related to domains of holomorphy and the boundary distance function

general-topology metric-spaces several-complex-variables

asked 46 mins ago qinxs 91

2

votes

1

answer

29

views

Isn't $ceil(xy/z) = floor((xy+y-1)/z)$ for any positive integers $x,y,z$?

integers ceiling-and-floor-functions

modified 49 mins ago jjagmath 7,037

0

votes

1

answer

13

views

supremum on quadratic and bilinear form

inner-products normed-spaces upper-lower-bounds

modified 52 mins ago Philipp123 625

-1

votes

1

answer

24

views

help understanding exponent simplications

algebra-precalculus exponential-function

answered 56 mins ago Rafael H. 62

2

votes

4

answers

23

views

Point A exists on line between B and C points. I got "x,y" coordinates of B and C points, but only "y" of point A. How to find missing "x" of point A

geometry coordinate-systems

answered 56 mins ago Ryan G 13.9k

0

votes

1

answer

20

views

Hamiltonian Cycle and Euler Cycle

graph-theory algorithms hamiltonian-path eulerian-path

answered 57 mins ago kabenyuk 2,899

2

votes

0

answers

32

views

How find unknown radius and density proportionality constant for a changing density cylinder?

mathematical-physics

modified 58 mins ago Aneikei 151

-1

votes

0

answers

5

views

PDE - Number of solutions to I.V.P

partial-differential-equations

asked 59 mins ago Alon 1,575

0

votes

0

answers

33

views

Thesis topics related to graph theory.

graph-theory computational-complexity cryptography network

modified 59 mins ago Henno Brandsma 213k

0

votes

0

answers

8

views

Hypercohomology of a direct image of a complex of sheaves

algebraic-geometry homology-cohomology homological-algebra sheaf-cohomology

asked 1 hour ago Flavius Aetius 412

2

votes

0

answers

63

views

Combining Covariances of Two Sets

statistics algorithms covariance

modified 1 hour ago Mike 160

0

votes

0

answers

14

views

Given a closed function f(x) with dom f open, if f converges to infinity as x converging to bd domf, does its L2-norm of gradient go to infinity?

real-analysis functions convex-optimization

modified 1 hour ago suineg 67

0

votes

0

answers

8

views

Difference between EPE and MSE

statistics machine-learning

modified 1 hour ago Federico Mondaini 29

0

votes

0

answers

12

views

What's the measure of the angle $PFB$ in the figure below?

euclidean-geometry plane-geometry

asked 1 hour ago peta arantes 2,293

0

votes

0

answers

6

views

On Simply-Connected

connectedness polyhedra

asked 1 hour ago John1970 81

0

votes

0

answers

24

views

How do I derive an Equation for the Pareto Distribution?

algebra-precalculus functions polynomials graphing-functions

modified 1 hour ago Weigeltisaur 1

0

votes

0

answers

28

views

Every descending chain of monomials is stationary.

abstract-algebra commutative-algebra

modified 1 hour ago user26857 46.1k

0

votes

0

answers

15

views

Continuity of bivariate function with both discrete and continuous variables

continuity

modified 1 hour ago PierreCarre 12.9k

3

votes

2

answers

39

views

Probability of randomly assigning elements to groups

probability combinatorics examples-counterexamples

modified 1 hour ago N. F. Taussig 61.7k

1

vote

1

answer

25

views

A increasing function between two directed sets doesn't guarantee a subnet

general-topology nets

modified 1 hour ago Calvin Khor 29.1k

0

votes

0

answers

9

views

Is there a solution or an approximation for a definite integral of the form exp(i cos(x-y))dx?

definite-integrals exponential-function trigonometric-integrals

asked 1 hour ago tzimhs panousis 5

0

votes

1

answer

33

views

Prove that the product of two lines equations is hyperbola

analytic-geometry conic-sections hyperbolic-equations

modified 1 hour ago Moishe Kohan 77k

3

votes

1

answer

60

views

Optimal numbering of vertices of a complete bipartite graph.

combinatorics discrete-mathematics graph-theory discrete-optimization bipartite-graphs

modified 1 hour ago kabenyuk 2,899

1

vote

0

answers

9

views

Maximal geodesically convex function interpolating three points on the hyperbolic plane

convex-analysis riemannian-geometry interpolation hyperbolic-geometry convex-geometry

asked 1 hour ago ccriscitiello 163

0

votes

0

answers

6

views

Asymptotically stable fixed point that cannot be certified by norm?

dynamical-systems lyapunov-functions

asked 1 hour ago Francisco 1

2

votes

2

answers

52

views

Solve inverse trig system

algebra-precalculus trigonometry

answered 1 hour ago Awkward 21

2

votes

0

answers

14

views

How to find the rotation matrix (with no x rotation) between two rotation matrices?

matrices rotations angle orientation kinematics

asked 1 hour ago pakornpp 21

-1

votes

0

answers

16

views

Question for a Context Free Grammar exercise

context-free-grammar programming

asked 1 hour ago MZO 1

1

vote

0

answers

12

views

Relation between distributions of linearly related random vectors.

probability probability-distributions random-variables random-matrices

asked 1 hour ago Yaz 43

0

votes

0

answers

19

views

Circle Packing - Average distance between a random point in a circle and the second, third, fourth, ... closest circle centre

geometry circles packing-problem

modified 1 hour ago ACB 1,431

1

vote

0

answers

14

views

Growth function $\tau_{\mathcal{H}}(m)$ lower bound

probability-theory statistics machine-learning

asked 2 hours ago bravoralph 159

1

vote

0

answers

27

views

Standard probability space, error in book "Integration and probability" by Paul Malliavin.

measure-theory

modified 2 hours ago Calvin Khor 29.1k

2

votes

1

answer

35

views

Problem involving Borel-Cantelli Lemma and Lim Sup of Sequences

probability-theory limsup-and-liminf borel-cantelli-lemmas

modified 2 hours ago Davide Giraudo 153k

5

votes

0

answers

27

views

Evaluate $\int_0^t e^{-\lambda s} \,\text{erf}(\ln(t-s))\,\text{d}s$?

integration definite-integrals special-functions convolution error-function

asked 2 hours ago MisterBlobfish 71

2

votes

1

answer

465

views

Non linear phase portrait

calculus matrices ordinary-differential-equations

modified 2 hours ago Ice Tea 345

1

vote

0

answers

42

views

irrationality and density of sets

dynamical-systems

modified 2 hours ago Asaf Karagila♦ 362k

1

vote

0

answers

13

views

Help in deriving Birkoff's theorem

coordinate-systems general-relativity

asked 2 hours ago Thomas 37

4

votes

1

answer

39

views

Well ordering on sequences over well-ordered sets

set-theory well-orders

modified 2 hours ago Asaf Karagila♦ 362k

0

votes

0

answers

14

views

Transform into predicate logic: "Every natural number is the sum of at most 4 squared natural numbers"

predicate-logic

asked 2 hours ago Hagai Lev Hacohen 9

3

votes

1

answer

56

views

Calculating $P(\sum X_i < \infty)$ for $X_i\sim U(0,1)$

sequences-and-series probability-theory convergence-divergence solution-verification borel-cantelli-lemmas

answered 2 hours ago Davide Giraudo 153k

0

votes

0

answers

9

views

General formula for normal curvature

differential-geometry curvature

asked 2 hours ago mathslover 812

3

votes

1

answer

28

views

Preimage of a homomorphism preserves the index?

group-theory group-isomorphism group-homomorphism

modified 2 hours ago GreginGre 10k

0

votes

0

answers

13

views

Finding the minimum value of a parameter that makes a curve non-simple.

complex-analysis complex-numbers complex-geometry

asked 2 hours ago coffee_pls 541

0

votes

0

answers

18

views

Deriving Fourier for $\int f$, when we know Fourier of $f$

real-analysis integration fourier-series uniform-convergence

asked 2 hours ago variations 781

2

votes

0

answers

35

views

Evaluate the limit $\lim_{x\rightarrow \frac{\pi}{2}}-(x-\frac{\pi}{2})\cdot\frac{ln(cos(x))}{x^2}$

calculus limits

modified 2 hours ago fredericoamigo 91

0

votes

0

answers

15

views

Is the standard name for a space of linear maps from one vector space into another?

vector-spaces dual-spaces

asked 2 hours ago koralgooll 253

0

votes

0

answers

17

views

Totally real field

number-theory

asked 2 hours ago Federico Romagnani 51

0

votes

0

answers

13

views

Radioactive decay (atoms decay do not independently)

mathematical-modeling

modified 2 hours ago Severin Schraven 14.1k

0

votes

1

answer

24

views

Inverse image of $Y$ and cardinality.

functions elementary-set-theory

modified 2 hours ago Arctic Char 11k

0

votes

0

answers

14

views

Compute limit of $a_n:=E[f(x_1)f(x_2)]$, for random $(x_1,\ldots,x_n)$ on unit-sphere in $R^n$ and any function $f$ with a jump discontinuity at $0$.

real-analysis probability spherical-coordinates concentration-of-measure

asked 2 hours ago dohmatob 7,806

2

votes

1

answer

16

views

Proving properties of the Multivariate Normal Distribution?

statistics proof-writing normal-distribution

answered 2 hours ago Yakov Sushenok 93

2

votes

1

answer

16

views

Isos of C*-algebras completely positive and contactive?

functional-analysis operator-algebras c-star-algebras

modified 2 hours ago JustDroppedIn 12.1k

4

votes

0

answers

30

views

$E[(Y_1-f(x))^2] \leq E[(Y_2-Y_1)^2]$

probability-theory measure-theory inequality stochastic-processes martingales

modified 3 hours ago Davide Giraudo 153k

1

vote

0

answers

20

views

Understanding Induction for Proving Inequalities

discrete-mathematics proof-writing solution-verification induction

asked 3 hours ago UnderMathUate 107

2

votes

0

answers

20

views

Properties of 3-cocycles

group-theory finite-groups group-cohomology

modified 3 hours ago kabenyuk 2,899

2

votes

0

answers

23

views

I'm having a problem with parallel transport which suggests the dimensionality is incorrect

differential-geometry

modified 3 hours ago Awkward 21

0

votes

0

answers

11

views

What conditions need to be met for matrices $A$ and $B$ to guarantee the correlation?

matrices matrix-decomposition matrix-rank correlation

asked 3 hours ago rongkoh 1

0

votes

0

answers

22

views

Show that $\limsup_{n \to \infty}a_n = \ell$ iff $\forall \varepsilon >0$ there are infinitely many indices $n$ for which $a_n > \ell - \varepsilon$.

real-analysis

asked 3 hours ago Salmiac 1

0

votes

1

answer

28

views

Question about multiplying a rank $1$ density matrix with a positive semidefinite matrix

linear-algebra matrices inequality matrix-equations trace

modified 3 hours ago lmaosome 568

1

vote

2

answers

3k

views

Write expressions using only NAND operator and prove logically equivalent?

discrete-mathematics logic propositional-calculus

modified 4 hours ago CommunityBot 1

1

vote

1

answer

23

views

Reading functions in local coordinates (vector bundles)

abstract-algebra general-topology continuity manifolds vector-bundles

answered 4 hours ago Jonas 321

3

votes

0

answers

17

views

I'm trying to find where a "3D logarithmic spiral" converges.

calculus linear-transformations

modified 4 hours ago Laxmi Narayan Bhandari 1,383

1

vote

1

answer

28

views

Regarding the Definition of an Orientable Foliation on a Manifold in terms of Transition Maps

manifolds smooth-manifolds orientation diffeomorphism foliations

modified 4 hours ago Neil hawking 1,912

2

votes

0

answers

42

views

Show that the alternating group $A_n$ is not perfect for $n \leq 4$

abstract-algebra group-theory finite-groups solvable-groups

modified 4 hours ago kabenyuk 2,899

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