Mathematics Stack Exchange

0

votes

0

answers

3

views

The variational equation

ordinary-differential-equations

asked 3 mins ago Saad ham 1

0

votes

1

answer

9

views

Proving a result when terms are in proportion

ratio

answered 5 mins ago Howard 1,546

-1

votes

0

answers

4

views

mathematical expectation after k iterations

probability expected-value

asked 6 mins ago Maruf Karaev 1

1

vote

1

answer

2k

views

Simplify ABC+AB'C+A'BC+A'B'C+A'B'C'

boolean-algebra

modified 7 mins ago Community♦ 1

0

votes

0

answers

2

views

Doubt on controllability and observability

dynamical-systems control-theory linear-control

asked 8 mins ago J.D. 155

1

vote

1

answer

51

views

How will matrix $A^n$ affect the original eigenvector and eigenvalue?

linear-algebra matrices eigenvalues-eigenvectors

modified 10 mins ago celtschk 36.3k

0

votes

0

answers

19

views

Integral inequality of quasi-integrable functions

measure-theory almost-everywhere

modified 12 mins ago h3fr43nd 91

0

votes

0

answers

2

views

Lyapunov exponent relationship with chaotic behavior

cryptography chaos-theory lyapunov-functions

asked 14 mins ago Theprince 23

0

votes

0

answers

3

views

Design Numbers on Dice

probability

asked 14 mins ago Benjamin 99

0

votes

1

answer

19

views

Derivation of a lagrangian from the equations of the motion

classical-mechanics euler-lagrange-equation lagrange-interpolation

modified 15 mins ago ms._VerkhovtsevaKatya 3,064

1

vote

1

answer

40

views

Crude upper bound for TV distance to stationarity for a Markov chain

real-analysis probability-theory markov-chains

modified 16 mins ago user8675309 1,064

2

votes

1

answer

17

views

$\arg(z_1 + z_2)$ if $z_1 = 2\cos\left(\frac{\pi}{12}\right)$ and $z_2 = 2i$

complex-numbers

modified 16 mins ago ms._VerkhovtsevaKatya 3,064

0

votes

0

answers

4

views

How do I prepare for the skill test based on this job role?

algorithms mathematical-modeling math-software career-development

asked 17 mins ago Math geek 376

1

vote

0

answers

20

views

Finding islands in a multiset

elementary-set-theory

modified 17 mins ago Pandazoic 49

0

votes

0

answers

7

views

Create Cayley table for ($\mathbb{Z}_{18}^*,\times)$

group-theory cayley-table

modified 1 min ago Dominik 193

0

votes

0

answers

7

views

How to compute $\int_{\varepsilon}^r \frac{1}{s^{n-2}}\int_{B(0,s)}Df(y)dy ds$?

real-analysis calculus analysis

asked 21 mins ago Bob Oakley 580

3

votes

2

answers

23

views

A converging trignometry series

convergence-divergence

modified 23 mins ago Qurultay 2,753

0

votes

2

answers

30

views

A simple equation involving trigonometry

trigonometry

answered 24 mins ago Atticus 4,603

0

votes

0

answers

7

views

For $x\in G$, define $H_x=\{g^{-1}xg \mid g\in G\}$. Under what conditions on $x$ will $H_x \leq G$. Further, if $H_x \leq G$, will $H_x \lhd G$?

abstract-algebra group-theory normal-subgroups

modified 25 mins ago Thomas Shelby 8,254

0

votes

2

answers

18

views

Inclusion in the ring of integers

algebraic-number-theory

modified 26 mins ago Dietrich Burde 94k

4

votes

2

answers

168

views

Countable sum of atomic measures is atomic?

measure-theory

modified 26 mins ago saz 96k

0

votes

1

answer

10

views

Cumulative function continuous but not strictly increasing

probability-theory statistics

answered 27 mins ago Will 1,213

1

vote

0

answers

5

views

Function tested with $C^1_0$ test functions

real-analysis measure-theory

asked 27 mins ago Leonardo 618

1

vote

1

answer

24

views

Application of the Girsanov theorem

probability-theory stochastic-calculus brownian-motion

modified 28 mins ago saz 96k

0

votes

0

answers

3

views

What are the consequences if the BSD conjecture is assumed to be false

number-theory elliptic-curves

asked 28 mins ago Safwane 3,236

0

votes

0

answers

5

views

Suppose P iff Q, P iff R. Also suppose Q and R never mean the same thing. What does this mean?

logic set-theory

asked 29 mins ago user81787 13

0

votes

1

answer

41

views

The geometric object given by a positive definite symmetric matrix?

calculus linear-algebra geometry differential-geometry

modified 31 mins ago peek-a-boo 7,194

0

votes

0

answers

56

views

For uncountable $X$ and countable $Y$, is there a bijection $X/Y\to X$? If not, what are the minimal conditions needed for a bijection?

group-theory elementary-set-theory

modified 32 mins ago user1729 22k

2

votes

2

answers

26

views

$|x+y|^p \leq |x|^p + |y|^p$ for $0 < p < 1$.

inequality

modified 32 mins ago Martin R 43.1k

0

votes

0

answers

1

view

Computing Galois Group of $\mathbb{Q}(2^{\frac{1}{4}}

galois-theory galois-extensions

asked 36 mins ago SunShine 767

3

votes

1

answer

206

views

On the research fertility of Arithmetic Topology.

reference-request knot-theory maximal-and-prime-ideals arithmetic-topology

answered 40 mins ago Guilherme Gondin 46

0

votes

0

answers

6

views

Generalised Estimating Equation (GEE) vs. Recurrent Neural Network (RNN)

statistics neural-networks

asked 41 mins ago Leockl 7

0

votes

0

answers

7

views

Any approximation or solution for integral of Macdonald Function multiplying by Exponential Function multiplying by Linear Function?

exponential-function approximation bessel-functions

asked 43 mins ago Ali Raza 29

0

votes

1

answer

26

views

How to solve a differential equation $y=xy'+\ln y',\ \ y(-1)=-1$

calculus ordinary-differential-equations

modified 44 mins ago Lutz Lehmann 78.8k

1

vote

1

answer

52

views

Compact and Minimal Imply $\epsilon$-dense

general-topology metric-spaces dynamical-systems compactness

modified 44 mins ago Alex Ravsky 51.8k

0

votes

2

answers

412

views

Unitary operator on infinite Hilbert space

functional-analysis

modified 45 mins ago celtschk 36.3k

0

votes

0

answers

10

views

Equation of path

calculus

asked 47 mins ago Partha Sarathi Purkayastha 9

0

votes

0

answers

4

views

definition of Hölder continuity

real-analysis analysis pde

asked 47 mins ago Harish 837

0

votes

1

answer

15

views

Help with induction using divisibility.

induction divisibility

modified 49 mins ago Joshua Cridland 1

1

vote

0

answers

5

views

Help Understanding The Concept of Full Rank Exponential Families.

statistics

asked 51 mins ago Chuong Nguyen 130

0

votes

1

answer

32

views

Show $P(A|B) > P(A|B^c)$ is equivalent to $P(B|A) > P(B|A^c)$

conditional-probability bayes-theorem

modified 58 mins ago Frousse 105

0

votes

0

answers

13

views

Negative Binomial Distribution transformation

probability negative-binomial

modified 1 hour ago Tomer 1

0

votes

1

answer

26

views

$\forall n \in \mathbb{N}, 2n \in A \Leftrightarrow 2n+1 \in A$ is a $\sigma -$algebra

measure-theory functions

answered 1 hour ago Henno Brandsma 150k

6

votes

1

answer

599

views

+100

KL Divergence between the sums of random variables.

probability information-theory

modified 1 hour ago Arnaud Mégret 436

1

vote

1

answer

24

views

Greatest value of $xz$ in expression

inequality

modified 1 hour ago Atticus 4,603

0

votes

0

answers

8

views

The proof of the Mean-value formulas for Laplace's equation in Evan's book

real-analysis calculus analysis pde

modified 1 hour ago Bob Oakley 580

3

votes

2

answers

17

views

If $\mu$ is an infinite cardinal, there is a function $f:\mu\longrightarrow\mu$ such that $f^{-1}[\alpha]$ is cofinal in $\mu$ for all $\alpha\in\mu$.

set-theory cardinals

answered 1 hour ago Vsotvep 3,610

1

vote

0

answers

30

views

Formula for Feigenbaum’s constant?

number-theory numerical-methods approximation conjectures continued-fractions

modified 1 hour ago Mr Pie 7,140

-3

votes

0

answers

24

views

Hey guys can you give me a real life problem with solution that involves derivatives

derivatives

asked 1 hour ago Tom Owen 1

1

vote

0

answers

17

views

Understanding DoCarmo's Proof $d(f^* \omega)=f^*(d \omega)$

manifolds differential-forms

asked 1 hour ago math student 137

0

votes

1

answer

8

views

Completion of $\sigma$-algbera is closed under complementation

measure-theory

answered 1 hour ago Henno Brandsma 150k

0

votes

0

answers

14

views

kernel and dimensionality

machine-learning

modified 1 min ago Rahim Tariverdi 1

0

votes

0

answers

16

views

Let $\sum a_n=s$ be conditional convergent, $\sum a_{f(n)}=t\neq s$. Show $\forall\ N, \exists\ n$, such that $|n-f(n)|>N$.

sequences-and-series conditional-convergence

modified 1 hour ago xldd 2,619

4

votes

0

answers

32

views

Probability of random sphere lying inside the unit ball

probability geometry spheres geometric-probability

modified 1 hour ago joriki 188k

0

votes

0

answers

13

views

Applications of system radical equation [closed]

systems-of-equations

asked 1 hour ago Như Quỳnh 1

1

vote

1

answer

21

views

Eigenvalues of $5 \times 5$ matrix with real entries from given condition

linear-algebra eigenvalues-eigenvectors characteristic-polynomial

modified 1 hour ago amWhy 196k

2

votes

0

answers

11

views

Prove that rank(A) = rank(A|C)

linear-algebra systems-of-equations matrix-rank

asked 1 hour ago Tom Lamensia 21

0

votes

1

answer

15

views

volume of a solid with a cylindrical hole

volume multiple-integral

modified 1 hour ago TeriyakiNinja 15

0

votes

0

answers

15

views

Square of the angle bisector in a triangle.

geometry triangles

modified 1 hour ago Aniket Gupta 463

4

votes

1

answer

63

views

Prove $PQ || HF$

geometry

modified 1 hour ago mengdie1982 9,213

1

vote

0

answers

39

views

Let $f:(0,\infty)\to\mathbb{R}$ be a continuous function such that for all $x\in(0,\infty)$.

real-analysis solution-verification

modified 1 hour ago Keen-ameteur 3,051

0

votes

0

answers

17

views

Joint PMF based on another variable's PMF

probability probability-theory discrete-mathematics

modified 1 hour ago speedy_catch 27

1

vote

0

answers

42

views

Compute the level of the Galois representation

algebraic-geometry algebraic-number-theory elliptic-curves galois-representations

modified 1 hour ago Abdallahchaibeddrraa 123

0

votes

1

answer

25

views

Why $W\cap V\neq\emptyset$ in this proof?

general-topology proof-explanation

answered 1 hour ago José Carlos Santos 250k

0

votes

0

answers

5

views

The implication of a coercive function

optimization

asked 1 hour ago Ridwan Pandiya 1

4

votes

1

answer

43

views

Find the biggest value of $|a-b|+|b-c|+|c-a|$ when $a^2+b^2+c^2=1$

inequality contest-math

answered 2 hours ago Atticus 4,603

10

votes

2

answers

2k

views

Folland, Chapter 1 Problem 17

measure-theory

modified 2 hours ago hamid kamali 2,971

0

votes

0

answers

11

views

Some integrals in the proof of the Poisson equation in EVAN'S TEXTBOOK

real-analysis calculus analysis pde

asked 2 hours ago Bob Oakley 580

0

votes

0

answers

20

views

Why is $E(Y|X)$ is projection of $Y$(so that error is zero) on plane containing all functions of X and passing through origin?

linear-algebra probability-theory hilbert-spaces statistical-inference conditional-expectation

modified 2 hours ago Nascimento de Cos 317

0

votes

0

answers

17

views

Almost sure convergence of posterior distribution to parameter and Independence

probability statistics

modified 2 hours ago OOESCoupling 125

0

votes

0

answers

10

views

this system contain an equilibrium in the set $\{ (x,y,z)\;:\; x+y+z=1,\; x,y,z\geq 0\}$

functional-analysis ordinary-differential-equations dynamical-systems

asked 2 hours ago Dani 33

1

vote

0

answers

31

views

Method of solving non-linear, first-order differential equation

ordinary-differential-equations nonlinear-system transcendental-equations

modified 2 hours ago Oyvach 99

0

votes

0

answers

14

views

Definite integral of Gaussian times $e^{-e^{-x}}$

integration

asked 2 hours ago user16320 354

0

votes

0

answers

17

views

Is the chain map linear

algebraic-topology

modified 2 hours ago Asukev 1

1

vote

1

answer

12

views

Vectorizing blocks of bilinear form

linear-algebra matrices bilinear-form

answered 2 hours ago Morgan Rodgers 11.1k

0

votes

0

answers

22

views

How many ways can the marbles be distributed so that each person gets 3n marbles?

probability

asked 2 hours ago AezAce 1

2

votes

1

answer

24

views

Eigenvalue of sum of two specific matrices

linear-algebra eigenvalues-eigenvectors spectral-theory

answered 2 hours ago user1551 89.9k

1

vote

0

answers

18

views

Why are the definitions of subtangent and subnormal different in Cartesian and polar systems?

calculus geometry

modified 3 hours ago BibThePhysicist 179

1

vote

1

answer

19

views

Interesting License Plate Question - Odds of seeing same ending four digits on 10 different cars

probability sequences-and-series statistics

answered 3 hours ago Shiv Tavker 67

4

votes

1

answer

741

views

Why is the square root of Cholesky decomposition equal to the lower triangular matrix?

linear-algebra matrices eigenvalues-eigenvectors kalman-filter

modified 3 hours ago Community♦ 1

0

votes

0

answers

9

views

What is the “unicital complement” of a collection of subsets really called, and which lowersets $(\lambda^{\perp})^{\perp}= \lambda$?

terminology order-theory

modified 3 hours ago William Elliot 13.8k

7

votes

0

answers

69

views

Is $\sum_{n=1}^{\infty} \frac{1}{\operatorname{lcm}[1,~2,~\ldots,~n]}$ irrational?

sequences-and-series number-theory summation irrational-numbers gcd-and-lcm

modified 3 hours ago Andrew Ostergaard 3,737

0

votes

1

answer

11

views

Building new charts for 2-differential

complex-analysis differential-forms riemann-surfaces

answered 3 hours ago Ted Shifrin 75.6k

0

votes

0

answers

10

views

Specific Coloring of Cube with 3 colors

abstract-algebra combinatorics permutation-cycles

asked 3 hours ago nickoba 249

0

votes

0

answers

11

views

Stable unstable equilibrium of a cone on an inclined plane

classical-mechanics

asked 3 hours ago Sharmi C 117

0

votes

0

answers

14

views

How can we differentiate indefinite integrals?

multivariable-calculus pde

asked 3 hours ago RandomWordMashup 1

0

votes

0

answers

6

views

Generalized inverse close to origin

linear-algebra generalized-inverse

modified 4 hours ago U S K Sullia 55

2

votes

0

answers

22

views

Question about interpretation of $[T]_\beta$ In determinant

linear-algebra determinant

asked 4 hours ago neveryield 131

1

vote

0

answers

9

views

a matrix condition that involves when a set of polynomials can have GCD as $1$

linear-algebra ring-theory

asked 4 hours ago am_11235... 854

1

vote

0

answers

19

views

symbolic definition of bijection?

functions

asked 4 hours ago DataInTheStone 21

0

votes

1

answer

12

views

Probability that graph is bipartite in Erdős–Rényi model with constant probability.

random-graphs

modified 4 hours ago saulspatz 30k

0

votes

1

answer

22

views

limit of an infinite sum of a random sequence of -1 and 1

sequences-and-series limits

answered 5 hours ago Reveillark 7,034

1

vote

1

answer

36

views

Find the absolute maximum and minimum of $f(x) = \frac{1}{x} - \frac{2}{x^2}$ on $[-2,1]$

calculus derivatives solution-verification

modified 5 hours ago Eric Towers 45.6k

1

vote

1

answer

91

views

C$^*$-Algebra Beginner's Questions

c-star-algebras

modified 5 hours ago Martin Argerami 143k

33

votes

3

answers

657

views

+250

How many ways are there to eat a chocolate bar?

combinatorics recreational-mathematics

answered 6 hours ago J Swanson 1,029

1

vote

4

answers

53

views

Show that $(\mathbb{Z}_{n} \times \mathbb{Z}_{n} , +)$ is not isomorphic to $ (\mathbb{Z}_{n^{2}} , +)$

group-theory solution-verification alternative-proof group-isomorphism

answered 7 hours ago Chris Custer 24.9k

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