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2

votes

2

answers

2k

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if $\{a_n\}$ converges to $a$ and $\{b_n\}$ converges to $b$ where $a_n\leq b_n$, show $a\leq b$

analysis limits inequality proof-verification

modified 5 mins ago CitizenSnips 113

0

votes

0

answers

3

views

Vector force application question about stationary objects

algebra-precalculus

asked 6 mins ago worrior v1 1

5

votes

0

answers

30

views

No bounded surjective linear map $L^{\infty} \to L^1$

functional-analysis lp-spaces

modified 7 mins ago WeakestTopology 553

0

votes

1

answer

15

views

Prove the superposition principle for 2nd order linear homogeneous ODEs, that is: if y1 and y2 are solutions of y'' +p(x)y' +q(x)y = 0 then,

ordinary-differential-equations

modified 8 mins ago Axion004 1,770

3

votes

1

answer

24

views

Why $k[[x^2,x^3]]$ is dimension 1 obvious?

abstract-algebra algebraic-geometry commutative-algebra

answered 9 mins ago Eric Wofsey 210k

1

vote

1

answer

28

views

Best straight-line approximation for $\sin(2x)$ on $(-\pi,\pi)$

linear-algebra least-squares

modified 10 mins ago Quanto 1,638

0

votes

1

answer

19

views

How to interpret the definition of well-ordered set in analysis I - Tao?

analysis

answered 13 mins ago Tanner Swett 6,104

1

vote

1

answer

13

views

How to set positive-definite function to be equal to the length of inputs?

linear-algebra functions positive-definite

answered 16 mins ago Omnomnomnom 133k

1

vote

0

answers

23

views

Inner product preserving mapping

linear-algebra matrices

modified 20 mins ago induction601 1,322

0

votes

1

answer

29

views

Trouble derivating an equation with matrices and vectors.

calculus matrices derivatives

answered 21 mins ago greg 11.6k

0

votes

0

answers

15

views

Define $f : L2 \rightarrow \mathbb{R}$ by $f(x) = \sum_{n=1}^{\infty} \frac{x_n}{n}$. Is $f$ continuous?

real-analysis

asked 22 mins ago Aphyd 89

1

vote

1

answer

16

views

Existence of nonsimilar matrix with same properties.

real-analysis linear-algebra abstract-algebra diagonalization

modified 28 mins ago SRJ 2,024

4

votes

1

answer

36

views

Normal Complement to a Sylow $2$-subgroup in a group of order $4$ mod $8$.

group-theory reference-request finite-groups normal-subgroups sylow-theory

modified 28 mins ago vginhi 28

1

vote

1

answer

28

views

Limitations on the difference of coprime composites less than $n^2$ for ascertaining primality?

combinatorics elementary-number-theory prime-numbers prime-factorization

modified 29 mins ago John Omielan 10.8k

1

vote

0

answers

26

views

Condition on a mutually singular measure

proof-verification lebesgue-measure radon-nikodym singular-measures

modified 30 mins ago CitizenSnips 111

1

vote

1

answer

14

views

Examples of mathematical ideas motivated by economics

soft-question economics

answered 34 mins ago BAYMAX 3,245

0

votes

0

answers

15

views

A polynomial in disguise. What am I missing conceptually?

algebra-precalculus polynomials

asked 34 mins ago Ultradark 565

1

vote

2

answers

30

views

Elements squaring to zero form an ideal in $\mathbf{Z}/n\mathbf{Z}$

modular-arithmetic ideals nilpotence

modified 37 mins ago Geoffrey Trang 822

3

votes

1

answer

67

views

Recursive formula to find the number of natural numbers in which there are no two adjacent even digits.

combinatorics discrete-mathematics computer-science

modified 37 mins ago Somos 17.6k

0

votes

1

answer

33

views

Approximation of a matrix finite geometric series

matrices algebra-precalculus approximation

modified 38 mins ago Karim 1

0

votes

0

answers

6

views

Generalization of digit-wise divisibility lemmas

group-theory number-theory prime-numbers modular-arithmetic

asked 42 mins ago Max von Hippel 119

4

votes

1

answer

56

views

Probability that graph with $6$ vertices and $5$ edges has a triangle.

probability

answered 43 mins ago quasi 40.4k

1

vote

0

answers

42

views

Image of compacts sets under a pseudo-continuous functions is bounded

general-topology set-theory compactness

modified 45 mins ago Gödel 1,618

-3

votes

0

answers

18

views

Probability, mean and standard deviation dice roll

probability

modified 47 mins ago David G. Stork 14.1k

3

votes

1

answer

40

views

How to find the value of Grandi's series using Ramanujan's summation

calculus sequences-and-series divergent-series ramanujan-summation

answered 48 mins ago CyclotomicField 2,886

0

votes

1

answer

9

views

What is the difference between initial conditions and input of system?

ordinary-differential-equations mathematical-modeling

answered 48 mins ago David G. Stork 14.1k

2

votes

2

answers

33

views

Locus of mid point of $AB$

analytic-geometry

modified 49 mins ago amd 36.2k

0

votes

1

answer

11

views

Is “3-QBF” defined similarly to 3-SAT is PSPACE-complete?

computational-complexity quantifiers np-complete satisfiability

modified 51 mins ago Kyle Jones 1,358

0

votes

3

answers

24

views

What does $H=\{h\mid h:X\rightarrow Y\}$ mean?

functions notation

answered 53 mins ago Chris Custer 18.9k

4

votes

2

answers

18k

views

How to find the transition matrix for ordered basis of 2x2 diagonal matrices

linear-algebra matrices change-of-basis

modified 58 mins ago Community♦ 1

0

votes

0

answers

18

views

sum function of power series $\sum_{n=0}^{\infty}\frac{(2n)!!}{(2n+1)!!}x^{2n+1}$

sequences-and-series summation

asked 1 hour ago Xin 9

0

votes

0

answers

6

views

BFGS in comparison with Gaussian newton

optimization

asked 1 hour ago user3289737 1

22

votes

5

answers

3k

views

Is there a known non-euclidean geometry where two concentric circles of different radii can intersect? (as in the novel “The Universe Between”)

geometry soft-question circles big-list noneuclidean-geometry

modified 1 hour ago Yly 7,619

0

votes

0

answers

9

views

A question about Polya's urn scheme

probability probability-theory

asked 1 hour ago manifolded 683

0

votes

0

answers

17

views

Counterpart of dominating sets in graphs

graph-theory reference-request

modified 1 hour ago Alex Ravsky 48.8k

0

votes

0

answers

8

views

Finding inverses of $\mathbf{A}$ using its $\mathbf{QR}$ factorization?

linear-algebra

modified 1 hour ago Fac Pam 271

0

votes

2

answers

10

views

Question about the sketch of a parametric curve

parametric

answered 1 hour ago Steve Kass 12k

0

votes

0

answers

9

views

Loop over a set $\mu_i$

statistics

modified 1 hour ago netotz 1

0

votes

2

answers

25

views

What is the image of a point without a defined line of reflection?

reflection

modified 1 hour ago CyclotomicField 2,886

0

votes

1

answer

14

views

Modelling infectious diseases without Immunization not yielding intuitive answer

calculus ordinary-differential-equations initial-value-problems

answered 1 hour ago Robert Israel 346k

0

votes

1

answer

55

views

Check the convergence of $\sum_{n=1}^{\infty} \int_{0}^{1/n} \sqrt {x}/ (1+x^{2})dx$

sequences-and-series

modified 1 hour ago Cragfelt 191

3

votes

1

answer

66

views

Curious closed forms of the $q$-Gamma function.

special-functions analytic-number-theory closed-form infinite-product q-analogs

answered 1 hour ago user153012 6,651

1

vote

0

answers

10

views

Uniform $C^k$ bounds from a Laplacian bound.

differential-geometry pde complex-geometry elliptic-equations

asked 1 hour ago hedgehog enthusiast 198

0

votes

0

answers

16

views

Coupon Collector Problem Markov Chain Interpretation

markov-chains expected-value coupon-collector

asked 2 hours ago arnavlohe15 16

0

votes

1

answer

12

views

Help with solving an optimization problem, connecting surface area and volume.

multivariable-calculus optimization

modified 2 hours ago DrMolo 30

0

votes

1

answer

25

views

If $F$ is representable, then $G$ is representable? If $G$ is representable, then is $F$ representable?

category-theory

answered 2 hours ago Derek Elkins 20.3k

0

votes

0

answers

11

views

direct product decomposition from orbits

group-theory finite-groups group-actions

modified 2 hours ago self-educator 134

4

votes

0

answers

62

views

Prove the following stopping time Cannot be a predictable stopping time.

probability-theory measure-theory stopping-times

modified 2 hours ago Amira 60

1

vote

2

answers

27

views

Is this correct way of solving this taks that relates to integral calculus

integration definite-integrals

modified 2 hours ago Axion004 1,770

0

votes

0

answers

5

views

Data processing inequality for KL divergence

stochastic-processes information-theory

asked 2 hours ago user1936752 622

0

votes

0

answers

19

views

Passing from Homology relative integers to $\mathbb{Z}_p$ loses topological information

algebraic-topology soft-question

asked 2 hours ago Mathematical Mushroom 1,089

0

votes

0

answers

6

views

what can be interpreted from residual graph?

regression

asked 2 hours ago ming 46

22

votes

0

answers

357

views

+100

Limit associated with a recursion

probability sequences-and-series number-theory recreational-mathematics recursion

modified 2 hours ago Vincent Granville 430

1

vote

0

answers

17

views

The field of fractions of $\mathbb{R}[x,y]/(x^2+y^2-1)$ is $\mathbb{R}(x)[y]/(x^2+y^2-1)$

abstract-algebra ring-theory commutative-algebra ideals

asked 2 hours ago user682705 154

1

vote

1

answer

45

views

Name of a property in Graph Theory

graph-theory terminology

answered 2 hours ago zahl 123

2

votes

1

answer

15

views

Extension of linearly independent set to a basis of a free module over a quotient of a Dedekind domain

commutative-algebra modules dedekind-domain free-modules

modified 2 hours ago Liam Baker 53

2

votes

0

answers

16

views

Quadratic Twists of Hyperelliptic Curve

number-theory algebraic-geometry elliptic-curves algebraic-curves arithmetic-geometry

asked 2 hours ago Ashvin Swaminathan 1,862

0

votes

0

answers

8

views

Finding projection direction from multiple tilted planes.

geometry 3d classical-mechanics projection

asked 2 hours ago WesH 1

1

vote

0

answers

15

views

How to find a triangularizing basis?

linear-algebra matrices linear-transformations

modified 2 hours ago Benny 16

0

votes

0

answers

16

views

An autonomous system that is asymptotically stable is not also exponentially stable.

dynamical-systems examples-counterexamples

modified 2 hours ago AzJ 187

2

votes

1

answer

41

views

Checking whether the usage of Fubini's theorem is possible

complex-analysis analysis

modified 2 hours ago Kavi Rama Murthy 109k

1

vote

0

answers

20

views

Winning strategies for games on the natural numbers

combinatorics set-theory ramsey-theory

asked 2 hours ago user-1 66

0

votes

1

answer

18

views

How to map “smooth hills” to “bumpy” hills?

geometry functions graphing-functions almost-periodic-functions

answered 2 hours ago DinosaurEgg 1,900

1

vote

0

answers

61

views

Proving $f(x_1)\leq f(x_2)$ in the following context

linear-algebra matrices eigenvalues-eigenvectors matrix-equations matrix-calculus

modified 2 hours ago Jef 11

2

votes

0

answers

21

views

GAP — NullspaceModQ not working

gap

modified 2 hours ago Alexander Konovalov 5,434

0

votes

1

answer

12

views

Hamiltonian symplectomorphism

symplectic-geometry

answered 2 hours ago Mindlack 7,421

4

votes

1

answer

1k

views

Derivation of poisson kernel for disk of radius $R$ from unit disk

real-analysis complex-analysis analysis

modified 2 hours ago Community♦ 1

0

votes

2

answers

63

views

Is there a function f with $ f (x) $ divergent for large x and slower than logarithmic growth rates?

real-analysis calculus logarithms asymptotics

modified 2 hours ago Daniel Camarena Perez 597

10

votes

1

answer

168

views

Largest Numerator of Sum of Egyptian Fractions

number-theory recreational-mathematics fractions

modified 2 hours ago Woett 454

3

votes

1

answer

19

views

The succession of the coefficient theorem is split but not naturally

abstract-algebra general-topology algebraic-topology homology-cohomology homological-algebra

answered 3 hours ago Max 22.7k

0

votes

0

answers

10

views

Problem with finding the expected value of a trajectory under a constraint

probability numerical-methods numerical-optimization constraints

asked 3 hours ago 655321 348

1

vote

0

answers

45

views

Meaning of this mathematical symbol

notation tensors

modified 3 hours ago Robert Shore 5,689

0

votes

0

answers

6

views

measuring flip-flop behaviour across several topics

numerical-methods

asked 3 hours ago Ghanem 106

2

votes

2

answers

7k

views

Proof of orthogonal matrix property: $A^{-1} = A^t$

linear-algebra matrices orthogonality orthogonal-matrices

modified 3 hours ago nbro 2,547

0

votes

0

answers

12

views

Find image of $T$ in the $xy$ plane under the following transformation

multivariable-calculus coordinate-systems

asked 3 hours ago chilliefiber 142

2

votes

1

answer

33

views

Direction of least change of a scalar/vector function

vector-analysis vector-fields scalar-fields

answered 3 hours ago demiralp 11

0

votes

1

answer

18

views

What does Singular value represent in the context of Singular Value Decomposition

linear-algebra svd

answered 3 hours ago Ian 70.6k

1

vote

1

answer

26

views

Asymptotic behaviour of heat equation solution

pde summation heat-equation

answered 3 hours ago Mostafa Ayaz 19.1k

7

votes

1

answer

53

views

Products of Determinantal Ideals

matrices algebraic-geometry commutative-algebra determinant

answered 3 hours ago Minseon Shin 1,835

0

votes

0

answers

20

views

When the Solutions of a System of Recurrence Relations converge

eigenvalues-eigenvectors recurrence-relations

modified 3 hours ago jonan 82

6

votes

1

answer

76

views

A covering space in $\Bbb R^3$ exists iff there is an embedding $M_g$ of the 3-torus which induces a surjection

algebraic-topology covering-spaces

modified 3 hours ago Camilo Arosemena-Serrato 6,083

0

votes

0

answers

25

views

Integration of periodic function

real-analysis calculus integration

asked 3 hours ago Gustave 745

0

votes

0

answers

9

views

An explicit presentation for the graded $\mathbb{Z}[1/N]$-algebra of modular forms

modular-forms

asked 3 hours ago hello 133

3

votes

1

answer

3k

views

My Moore and Mealy machines look the same. Why?

automata

modified 3 hours ago Community♦ 1

6

votes

2

answers

137

views

Prove or disprove that there does not exist a monotone function $f:\mathbb{R}\rightarrow\mathbb{Q}$ which is onto.

real-analysis monotone-functions

modified 4 hours ago Robert Shore 5,689

2

votes

0

answers

44

views

Euler-Poincare characteristic for relative schemes

algebraic-geometry schemes sheaf-cohomology coherent-sheaves

modified 4 hours ago Dubious 3,488

0

votes

0

answers

24

views

Equivalence of measurability? What is the advantage of each of these?

real-analysis measure-theory definition

asked 4 hours ago Hawk 5,715

8

votes

1

answer

80

views

Generalizing Archimedes' “The Quadrature of the Parabola”

calculus integration geometry ordinary-differential-equations integral-equations

modified 4 hours ago Aretino 27.5k

1

vote

0

answers

30

views

Finding parameters for function to be integrable

integration functions definite-integrals indefinite-integrals riemann-integration

modified 4 hours ago cmk 5,814

4

votes

3

answers

65

views

Solve $\frac{1}{x}z_x+\frac{1}{y}z_y=4$

pde boundary-value-problem characteristics

modified 4 hours ago Axion004 1,770

5

votes

3

answers

321

views

Selfish Trolley Car Debate

probability

modified 4 hours ago user144527 424

4

votes

0

answers

41

views

What functions satisfy one of these equalities: $x \cdot \Phi(x) = (\Phi \ast \Phi)(x)= \int_{- \infty}^{x} \Phi(t) dt$?

functional-equations

modified 5 hours ago Viktor Glombik 2,392

0

votes

0

answers

6

views

Implication and symmetric relations

relations

asked 5 hours ago Laur155 155 8

0

votes

0

answers

9

views

Boolean matrix factorization when a set of possible factors is known

matrices matrix-decomposition

modified 5 hours ago Rodrigo de Azevedo 13.4k

0

votes

0

answers

21

views

An improper integral involving Modified Bessel Function of the second kind

improper-integrals special-functions bessel-functions

modified 5 hours ago Andy Walls 1,878

0

votes

0

answers

18

views

+50

Final Question - Part 2 (Branching Process $Z_0 = 8$. Find $P(Z_2 =0)$)

probability probability-theory statistics stochastic-processes markov-chains

modified 6 hours ago soobster 320

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