Mathematics Stack Exchange

0

votes

0

answers

2

views

Exponential equation that's been bothering me

algebra-precalculus

asked 3 mins ago Hareka 1

1

vote

1

answer

26

views

Is this $\zeta(p)=\sum_{k\geq1 ,p\in \mathbb{P}}\frac{1}{{\sigma}_k(p)-1}$ true with sigma is power of sum divisor function?

prime-numbers riemann-zeta divisor-sum

modified 3 mins ago daniel 6,284

0

votes

0

answers

2

views

algebras_associative_problems_hard

algebras

asked 4 mins ago Chipa-Chipa2 1

0

votes

0

answers

3

views

Matrix formation

matrices permutations combinations

asked 4 mins ago Dhruv Deshmukh 12

-1

votes

1

answer

7

views

What is the vector form of Taylor series expansion?

calculus vectors taylor-expansion

answered 5 mins ago Klaus 2,732

0

votes

0

answers

2

views

Is this unipotent group, over characteristic 2, connected?

algebraic-geometry algebraic-groups positive-characteristic

asked 5 mins ago simplequestions 352

0

votes

0

answers

10

views

Regarding the construction of quotient category

category-theory homological-algebra abelian-categories

modified 6 mins ago Later 33

0

votes

0

answers

4

views

Why we cannot attribute the length to probability in this example?

probability-theory measure-theory

asked 7 mins ago arash 1

0

votes

0

answers

15

views

Triple scalar product

vectors

modified 8 mins ago Eric Toporek 100

0

votes

1

answer

25

views

Is $S = \{(x,y,z) \in \mathbb{R}^3: \sqrt{(x^2+y^2)} \leq z \leq 1\}$ bounded, compact and/or path connected?

multivariable-calculus

modified 9 mins ago Eric Toporek 100

0

votes

0

answers

15

views

Prove that $x = y$ where $f(x) = f(y)$.

algebra-precalculus

asked 13 mins ago Lê Thành Đạt 223

0

votes

1

answer

12

views

Prove and interpret $|f(x)+g(x)|=|f(x)|+|g(x)| \implies f(x)g(x)\geq0$

algebra-precalculus inequality

answered 14 mins ago rb612 1,863

0

votes

2

answers

14

views

Two line segments inside a regular pentagon forms the same angle with the sides of this pentagon. What is the length of x in the picture?

geometry polygons

answered 16 mins ago Michael Rozenberg 109k

0

votes

1

answer

11

views

Provide third order Taylor expansion of stable manifold near a saddle point in a dynamical system.

ordinary-differential-equations manifolds taylor-expansion dynamical-systems

modified 16 mins ago JJacquelin 45.1k

0

votes

1

answer

9

views

How to show that $($grad $F)(a,b,c)$ is normal to $r^2=a^2+b^2+c^2$ at $(a,b,c)$?

vector-analysis

modified 18 mins ago Stefan Octavian 175

0

votes

1

answer

27

views

Prove that $\forall A_k\subset \{1,2,\dots,3n\}$, with $|A_k|=2n$, $\exists (a_i,a_j)\in A_k$ s.t. $a_i-a_j=n-1$

combinatorics discrete-mathematics pigeonhole-principle

modified 19 mins ago rtybase 11.5k

0

votes

0

answers

11

views

The absolute of the expression$\frac{1+\sqrt3 \tan 1^o}{\sqrt3 -\tan 1^o} \cdot \frac{\tan 89^o}{\cot 3^o}$ is equal to…

trigonometry

asked 19 mins ago rash 538

0

votes

1

answer

13

views

Probability of mutually Independent events

probability

answered 19 mins ago rb612 1,863

0

votes

0

answers

7

views

Calculation of Profit and range

contest-math

modified 19 mins ago Kanpur 1

2

votes

1

answer

33

views

Clarification of notation used in differential games

notation dynamical-systems game-theory optimal-control differential-games

answered 20 mins ago lonza leggiera 1,153

0

votes

2

answers

17

views

Probability of 3 Events - Standard Card Deck

probability

modified 22 mins ago BJKShah 45

0

votes

2

answers

16

views

A question about fixed points and non-expansive map

functional-analysis fixed-point-theorems

modified 22 mins ago GSofer 771

0

votes

0

answers

17

views

When is the kernel of the $(n-1)$-power map a proper subgroup?

abstract-algebra number-theory prime-numbers

modified 25 mins ago C.X.Neo 1

0

votes

0

answers

8

views

Characteristic Vector Question

discrete-mathematics characteristics bit-strings

modified 27 mins ago Minus One-Twelfth 2,823

1

vote

1

answer

16

views

Gaussian quadrature: Orthogonal polynomial for chi distribution

numerical-methods orthogonal-polynomials quadrature

answered 28 mins ago Count Iblis 8,437

0

votes

0

answers

6

views

Silver DDPG paper, what does the “d” mean here?

probability derivatives

asked 28 mins ago flexitarian33 1

18

votes

0

answers

1k

views

Finding a better approximation to a prime number relation

prime-numbers

modified 29 mins ago Adam 541

0

votes

0

answers

24

views

Zeroes of a sextic polynomial and analytical form

polynomials roots

modified 30 mins ago Emil 1

1

vote

0

answers

16

views

Finding an Orthogonal Complement of a Subspace

functional-analysis

modified 33 mins ago Chinnapparaj R 5,808

0

votes

1

answer

30

views

How to simplify and solve this integral?

integration

answered 42 mins ago Paras Khosla 2,553

3

votes

1

answer

31

views

Notes regarding Real analysis

reference-request soft-question

answered 42 mins ago Martín-Blas Pérez Pinilla 34.7k

0

votes

1

answer

40

views

Proving $z''_u+z''_v=(x^2+y^2)(z''_x+z''_y)$

multivariable-calculus partial-derivative

answered 43 mins ago Max 4,407

0

votes

3

answers

17

views

Square numbers related to square root

number-theory square-numbers

modified 45 mins ago st.math 601

1

vote

1

answer

27

views

Sum of all positive divisors are prime

prime-numbers divisor-sum

modified 46 mins ago Later 31

0

votes

0

answers

11

views

Uniform Isomorphism

general-topology uniform-continuity uniform-spaces

asked 47 mins ago Percy 71

0

votes

1

answer

16

views

What does the following complex equation signifies?

complex-analysis

modified 52 mins ago user3877518 1

0

votes

2

answers

23

views

Algebra problem that you have to assume certain criteria at the end.

algebra-precalculus functions functional-equations

modified 55 mins ago aman 56

0

votes

1

answer

13

views

Existence of diagnalizable matrix

linear-algebra matrices diagonalization

answered 57 mins ago Thinking 1,257

2

votes

3

answers

101

views

Intuition of generalized eigenvector.

linear-algebra intuition jordan-normal-form generalizedeigenvector

modified 57 mins ago Arthur 119k

0

votes

0

answers

8

views

Accrual probability

probability

asked 58 mins ago Parsnip 1

0

votes

0

answers

6

views

Find the conditional density

statistics conditional-probability

asked 58 mins ago Duaa Hamzeh 52

0

votes

1

answer

18

views

Combinatorial Proof (Argument)

combinatorics binomial-coefficients binomial-theorem

answered 1 hour ago richrow 268

2

votes

1

answer

24

views

Need help finding eigenvectors of matrix

linear-algebra matrices eigenvalues-eigenvectors

modified 1 hour ago Rodrigo de Azevedo 13.2k

0

votes

0

answers

38

views

If $x'=Ax$ and $y'=Ay$, does it mean that $x=y$?

linear-algebra ordinary-differential-equations

modified 1 hour ago Rodrigo de Azevedo 13.2k

0

votes

0

answers

10

views

(Geometric and arithmetic mean)How to prove the function $G(x)-\alpha A(x)$ is concave?

convex-optimization

modified 1 hour ago Noilyn 1

0

votes

0

answers

8

views

Poisson distribution problem certain confusions

poisson-distribution

modified 1 hour ago sc_ 291

0

votes

1

answer

10

views

Meaning of stable $CP^2$

group-theory notation automorphism-group grassmannian

modified 1 hour ago Later 31

0

votes

1

answer

15

views

Below is the graph of the derivative of a function $f$ which is continuous on all real numbers. Which one of the followings are always correct?

calculus derivatives

answered 1 hour ago Theo Bendit 20k

1

vote

1

answer

677

views

Sum of all numbers less than equal to X relatively prime to all number less than Y

elementary-number-theory algorithms prime-factorization

modified 1 hour ago Community♦ 1

0

votes

0

answers

7

views

Why does the concentration gradient point towards the area of lowest concentration?

vector-analysis mathematical-modeling

asked 1 hour ago Stefan Octavian 175

2

votes

1

answer

29

views

$ W_{0}^{2}(\Omega)=\{ f\in W_{0}^{1}(\Omega):\Delta f\in L^{2}(\Omega)\}? $

functional-analysis pde sobolev-spaces laplacian

answered 1 hour ago Marvin 2,591

0

votes

0

answers

7

views

Discrete Time Fourier Transform of x[n] = 1

fourier-analysis fourier-transform signal-processing

asked 1 hour ago Navin 11

0

votes

1

answer

12

views

Probability of picking animal from pond

probability

answered 1 hour ago Tojrah 225

3

votes

0

answers

15

views

Left and right adjoints of restriction in modules.

algebraic-geometry commutative-algebra modules adjoint-functors

asked 1 hour ago user277182 483

4

votes

1

answer

162

views

+50

Equal coloring of balanced ternary tree

combinatorics graph-theory trees

modified 1 hour ago Dap 19.1k

0

votes

1

answer

17

views

Problem regarding this proof of Chinese Remainder Theorem

number-theory elementary-number-theory modular-arithmetic chinese-remainder-theorem

answered 1 hour ago Wuestenfux 5,303

0

votes

0

answers

8

views

Composition of morphisms in Quotient category

category-theory homological-algebra abelian-categories

asked 1 hour ago solgaleo 76

0

votes

0

answers

8

views

A definition of right-continuous using monotone sequences.

real-analysis probability-theory

asked 1 hour ago hfx477346 1

0

votes

0

answers

11

views

What is gradient of $|f(x)|^p f(x)$

analysis multivariable-calculus

modified 1 hour ago Math Learner 327

0

votes

0

answers

6

views

Show that $\sup_{x_1, \dots, x_n \in \mathscr{X}}|\mathscr{F}(x_1, \dots, x_n)|=S(\mathscr{A}, n)$

statistics machine-learning

asked 1 hour ago acrob4t1 1

0

votes

0

answers

8

views

Finding weak derivative of a function in the real line

real-analysis calculus pde

asked 1 hour ago Jimmy Sabater 2,532

-2

votes

0

answers

12

views

Proof of integral of complex function f(z)=z

line-integrals

asked 1 hour ago Ruvik 42

1

vote

1

answer

22

views

Understanding infinite products convergence

convergence complex-numbers infinite-product entire-functions

answered 1 hour ago RRL 52.9k

0

votes

0

answers

7

views

Equivalent definitions of a limit

real-analysis limits analysis definition

asked 1 hour ago Leo 783

1

vote

1

answer

34

views

Sum of all values that satisfy $\frac{x^{x-3}}{x}=\frac{x}{x^\frac{4}{x}}$.

algebra-precalculus

modified 1 hour ago NoChance 3,767

1

vote

1

answer

40

views

What is the definition of spectral convergence?

numerical-methods

answered 1 hour ago Yan King Yin 461

0

votes

0

answers

21

views

Recurrence with non-fixed number of variables

multivariable-calculus inequality recurrence-relations asymptotics factorial

modified 1 hour ago Dudi Frid 33

1

vote

2

answers

40

views

Solve the pde with separation of variables.

pde

answered 2 hours ago DR LIN 21

0

votes

0

answers

23

views

Maximum Order of the product of two elements in a group

abstract-algebra group-theory gap

modified 2 hours ago Martin Sleziak 44.9k

2

votes

1

answer

30

views

An ideal is radical if and only if $x^2\in I\Rightarrow x\in I$

commutative-algebra ideals

modified 2 hours ago user26857 39.4k

1

vote

0

answers

28

views

A differential operator associated with a vector field on the torus

differential-geometry pde dynamical-systems linear-pde

modified 2 hours ago Martin Sleziak 44.9k

0

votes

0

answers

24

views

Epsilon-delta definition of continuity in two dimensions

real-analysis analysis functions continuity absolute-continuity

modified 2 hours ago High GPA 962

0

votes

0

answers

21

views

+150

Finding weak solutions of conservation law

pde

modified 2 hours ago Jimmy Sabater 2,532

3

votes

1

answer

43

views

Three dimensional Laplace equation with constant Temp. on one face. [Solution not satisfying BC]

proof-verification pde problem-solving heat-equation laplacian

modified 2 hours ago AEngineer 1,644

2

votes

1

answer

20

views

Deleting a point in a connected metric space with more than one point gives us a non-compact set.

general-topology proof-verification

modified 2 hours ago Henno Brandsma 113k

0

votes

0

answers

16

views

How do I obtain a solution of this Helmholtz equation?

integration pde harmonic-analysis linear-pde

modified 2 hours ago Rodrigo de Azevedo 13.2k

0

votes

0

answers

11

views

Minimize the pipe usage.

optimization problem-solving

asked 2 hours ago MaJoR21 101

2

votes

0

answers

32

views

Moments of the Quadratic Assignment Problem (QAP)

combinatorics permutations algorithms discrete-optimization

modified 2 hours ago Rodrigo de Azevedo 13.2k

2

votes

1

answer

64

views

A Double sum with something weird between the summations

summation

answered 2 hours ago eyeballfrog 6,854

0

votes

0

answers

11

views

Rigid body kinetic energy extra term

dynamical-systems cross-product

asked 3 hours ago slader 1

-1

votes

0

answers

18

views

Tensors and group theory

group-theory tensors complex-geometry spin-geometry

asked 3 hours ago Robin Raj 1

2

votes

1

answer

9

views

Compute the worst case time complexity of the following algorithm, for i = 1 to n do for j = i to n^2 do print (i, j).

discrete-mathematics computer-science computational-complexity

answered 3 hours ago marty cohen 74.6k

1

vote

0

answers

11

views

finding maximum value of BVP

pde heat-equation maximum-principle

asked 3 hours ago Jimmy Sabater 2,532

2

votes

1

answer

18

views

Is a union of closures of cells in a CW complex closed?

general-topology algebraic-topology cw-complexes

modified 3 hours ago kaba 242

1

vote

1

answer

680

views

Differentiation- proof by Induction

calculus induction chain-rule

modified 3 hours ago Community♦ 1

0

votes

0

answers

15

views

Basic conceptual idea of connections on vector bundles

riemannian-geometry vector-bundles connections

modified 3 hours ago Maxed 237

0

votes

2

answers

36

views

Proving $\log^n(n)=\omega(n^{\log(n)}) $

logarithms asymptotics computer-science

modified 3 hours ago Rócherz 2,986

0

votes

1

answer

20

views

Problem A.4 from An introduction to manifolds by Loring Tu

general-topology

modified 3 hours ago Matematleta 11.6k

0

votes

0

answers

8

views

Interpolation inequality for Holder continuous functions.

real-analysis pde holder-spaces interpolation-theory

asked 3 hours ago mudok 362

0

votes

0

answers

4

views

help finding the chromatic number for a graph with two blocks as subgraphs that share a single vertex

graph-theory

modified 3 hours ago onlydumbquestions 41

0

votes

0

answers

12

views

Change of basis of a lattice

linear-algebra abstract-algebra complex-numbers integer-lattices

modified 3 hours ago Amrat A 316

1

vote

0

answers

4

views

Computing global monodromy of branched covering of Riemann sphere

algebraic-curves riemann-surfaces covering-spaces

asked 3 hours ago Zach Effman 1,672

1

vote

0

answers

11

views

Compute $\lim_{r\to 0}\frac{1}{\pi r^2}\int_{S_h} F\cdot dx$ Compare this to the curl.

multivariable-calculus

modified 4 hours ago AColoredReptile 368

1

vote

0

answers

8

views

rotate 3d unit vector a, on plane of a and the j (up) axis

vectors

asked 4 hours ago Alice Jacka 6

2

votes

2

answers

114

views

Is there better series to calculate sinh and cosh

sequences-and-series trigonometry trigonometric-series

modified 4 hours ago Thomas Shelby 4,344

2

votes

0

answers

17

views

What is the mathematically appropriate and concise way of writing a constant added to a random number?

probability probability-theory probability-distributions notation sampling

asked 4 hours ago Masked 11

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