Mathematics Stack Exchange

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2

answers

12

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Calculating $E[Z(Z-1)(Z-2)(Z-3)]$ where $Z$ is Poisson

probability probability-distributions expected-value

modified 59 secs ago StubbornAtom 11k

0

votes

0

answers

6

views

On $\sum_{x=0}^\infty x^n r^x$

sequences-and-series closed-form geometric-series

asked 1 min ago jeremy909 754

0

votes

0

answers

6

views

Find solutions for the equation a^3 + b^3 = c^2 where in integers c≥b≥a≥1.

number-theory elementary-number-theory

asked 3 mins ago mathm4n 31

0

votes

0

answers

8

views

Statistics linear regression

linear-regression

modified 4 mins ago Streamline Astra 11

0

votes

0

answers

8

views

Is this representation isomorphic to the group?

group-theory representation-theory lie-groups

asked 4 mins ago SimoBartz 291

0

votes

0

answers

3

views

Rademacher complexity of linear function class with compact parameter space and support

probability statistics

asked 4 mins ago MONODA43 98

0

votes

1

answer

18

views

How to prove that $\lim _{\left(x,\:y\right)\to \left(1,\:0\right)}\log _x\left(x+y\right)$ doesn't exist?

calculus limits multivariable-calculus

answered 5 mins ago Paul 7,183

0

votes

1

answer

26

views

Time averages for a 2-dimensional harmonic oscillator

self-learning classical-mechanics average ergodic-theory

answered 5 mins ago John B 13.8k

1

vote

1

answer

23

views

Prove the following two statements about differentiability are equivalent

real-analysis calculus derivatives solution-verification

modified 5 mins ago Taroccoesbrocco 9,815

0

votes

1

answer

5

views

Bernoulli trials distributions

probability probability-distributions

answered 6 mins ago herb steinberg 6,272

0

votes

0

answers

5

views

Question regarding the cardinality of a set

combinatorics set-theory

asked 6 mins ago RandomMatrices 161

1

vote

0

answers

21

views

A holomorhic function $f $ in the unit disc such that $\lim_{z\rightarrow 1}f(z)$ does not exist

sequences-and-series complex-analysis taylor-expansion analytic-functions

modified 8 mins ago Thomas Andrews 141k

1

vote

1

answer

12

views

Find the matrix of the linear transformation $f^*$ on the orthonormal basis on which all the vectors are given.

linear-algebra linear-programming

modified 8 mins ago VIVID 1,283

-1

votes

1

answer

19

views

Find it adjoint $T^{*}$

functional-analysis banach-spaces normed-spaces

modified 8 mins ago Mathematics Rockstar 132

0

votes

1

answer

15

views

How to find a vector given the scalar triple product

vectors

modified 9 mins ago Rick 525

0

votes

1

answer

25

views

Find the Point C given 2 points and a distance in a 2 dimensional space.

geometry

modified 10 mins ago None 1

1

vote

1

answer

11

views

Why are the $p$-oldforms $f(z)$ and $f(pz)$ linearly independent at level $\Gamma_0(pN)$?

number-theory reference-request modular-forms

answered 10 mins ago reuns 40.9k

0

votes

0

answers

17

views

An inequality on a euclidien space

linear-algebra abstract-algebra algebra-precalculus inequality cauchy-schwarz-inequality

modified 10 mins ago Amine 11

3

votes

1

answer

17

views

Question about unclear definition of Ackermann-Péter function in Stanford Encyclopedia of Philosophy

computability recursive-algorithms ackermann-function

modified 11 mins ago Siegmeyer 213

0

votes

0

answers

20

views

If multiple people roll a die, what's the probability to roll the highest number?

probability

modified 11 mins ago Saket Gurjar 1,235

1

vote

2

answers

21

views

Pierre runs a game at a fair, where each player is guaranteed to win $10 - Die rolling question

probability statistics dice word-problem

modified 12 mins ago Alexey Burdin 1,937

0

votes

0

answers

9

views

Convex function: optimization

statistics optimization proof-writing convex-optimization

asked 12 mins ago Stochastic 1

0

votes

0

answers

11

views

Deduce that $\int_0^{\infty} \frac{x\,J_0(x)}{ \sqrt{x^2 + a^2}}\,dx $

complex-analysis bessel-functions

asked 14 mins ago Jordan Hernandez 1

0

votes

1

answer

10

views

Show the feasible set of convex functions is convex.

optimization proof-writing convex-optimization alternative-proof

modified 14 mins ago StubbornAtom 11k

0

votes

2

answers

24

views

Limit of sequence of series $a_n=\frac{1}{n}\sum_{j=1}^n\sqrt{\frac{j}{n}}$

sequences-and-series limits

answered 19 mins ago Sebpar 57

0

votes

0

answers

11

views

Problem of whether a given topological space can be realized as a topological product

general-topology algebraic-topology

asked 19 mins ago PrimeNumbers 85

1

vote

1

answer

16

views

Poisson kernel equivalence

complex-analysis harmonic-functions

modified 20 mins ago Martin R 47.1k

0

votes

0

answers

9

views

cross ratio definition

projective-geometry cross-ratio

asked 23 mins ago Arianna 21

0

votes

0

answers

9

views

Maximize area of n-gon circumscribed around unit circle

convex-optimization maxima-minima geometric-inequalities

modified 24 mins ago Juicer 51

0

votes

0

answers

4

views

Inequality based on location of roots

quadratics

asked 25 mins ago Akash Gautama 245

3

votes

2

answers

34

views

Find $g(x)$ if $f(x)= \begin{cases} -1, & -2 \leq x \leq 0 \\ x-1, & 0 < x \leq 2 \end{cases}$ and $g(x) = |f(x)| + f(|x|)$

functions solution-verification

answered 27 mins ago Pythagoras 2,452

0

votes

0

answers

24

views

Line integration in pauls notes calculus III

calculus multivariable-calculus vector-analysis

modified 28 mins ago EditPiAf 16k

0

votes

1

answer

23

views

Binomial Distribution vs. Profit

probability probability-distributions

modified 29 mins ago Leo Long Vu 3

-1

votes

1

answer

13

views

Can you show that one form of the solution is the following: Sec 2π/17 = (2+√17+√W-√Y) /2

puzzle polygons

modified 31 mins ago EOC52943 1

0

votes

0

answers

14

views

Find linear combination of matrices for solve matrix multiplication as scalar product of matrices

linear-algebra matrices linear-transformations

modified 32 mins ago Diego Ruiz 1

1

vote

0

answers

8

views

Name for the following combination of two Bernoulli trials ? $m$ trials with success prob $p$ and $n$ trials with success probability $1-p$

probability probability-theory probability-distributions

modified 32 mins ago Firefox1921 27

1

vote

0

answers

18

views

Rank of a linear transformation

calculus linear-algebra integration

asked 34 mins ago Patrick Collins 193

0

votes

0

answers

4

views

What's the strength of weakening induction in PA by relativizing it to naturals?

first-order-logic peano-axioms

asked 34 mins ago Zuhair 1,999

0

votes

3

answers

26

views

How to find the implicit differentiation of a fraction?

implicit-differentiation

answered 34 mins ago amd 45.3k

3

votes

0

answers

49

views

Can a null hypersurface be foliated by spacelike sections?

differential-geometry manifolds mathematical-physics general-relativity semi-riemannian-geometry

modified 34 mins ago user1620696 20.4k

5

votes

0

answers

83

views

A simple group with $|\operatorname{Syl}_p⁡ G| \le 6$ is cyclic

abstract-algebra group-theory finite-groups sylow-theory p-groups

modified 36 mins ago Ron Stuer 70

-1

votes

0

answers

24

views

How to prove this equations

theta-functions

modified 41 mins ago William Elliot 14.5k

0

votes

1

answer

17

views

$\lvert \lvert x_k \rvert \rvert \rightarrow \infty \quad \Longrightarrow \quad f(x_k) \rightarrow+\infty$ implies existence of global minimiser

real-analysis optimization

answered 45 mins ago Gae. S. 10.8k

2

votes

1

answer

20

views

Solve PDE $xzu_x+yzu_y-(x^2+y^2)u_z=0$ using characteristics method

partial-differential-equations characteristics

modified 46 mins ago EditPiAf 16k

2

votes

0

answers

15

views

What's the difference between turning points and points of inflection?

derivatives terminology

modified 48 mins ago J. W. Tanner 36.9k

1

vote

2

answers

17

views

contraction principle definition question

real-analysis

answered 49 mins ago Axion004 7,655

0

votes

1

answer

9

views

Cramer-Rao lower bound for exponential distribution

statistics

answered 52 mins ago tommik 61

1

vote

0

answers

11

views

Any advantages of using Gödel universal functions in proving unsolvability?

logic recursion computability recursive-algorithms

asked 57 mins ago user634426 1,871

0

votes

0

answers

16

views

Change of integration variables across two maps in space and time

integration multivariable-calculus tensors jacobian change-of-variable

modified 57 mins ago Cogicero 147

2

votes

0

answers

14

views

The modulus of Gamma function $\left| \Gamma(x+iy) \right|$ is strictly decreasing when $x \in (0,\frac{1}{2})$ for a fixed $y \in \mathbb{R_+}$

complex-analysis gamma-function monotone-functions

asked 58 mins ago Matey Math 1,609

5

votes

0

answers

58

views

Arrow's impossibility theorem simple proof and explanation

modified 58 mins ago Rodrigo 4,306

1

vote

0

answers

17

views

Complete Metric Space can be a Banach Space?

functional-analysis metric-spaces banach-spaces complete-spaces

asked 59 mins ago Mrcrg 344

2

votes

1

answer

24

views

Skolem form transformation

logic first-order-logic

answered 1 hour ago Taroccoesbrocco 9,815

0

votes

0

answers

19

views

Attempting to prove a conserved quantity for incompressible Navier-Stokes PDE

multivariable-calculus partial-differential-equations symmetry fluid-dynamics

modified 1 hour ago user142523 604

2

votes

1

answer

30

views

Monotonicity of the Lebesgue Integral

real-analysis measure-theory lebesgue-integral

modified 1 hour ago ilovebulbasaur 287

0

votes

1

answer

15

views

Minimizing Type I and Type II errors Simultaneously

statistics hypothesis-testing

answered 1 hour ago paulinho 2,436

1

vote

1

answer

14

views

Prove that PDE $u_t+x^2u_x=0$ has infinite solutions

analysis partial-differential-equations characteristics transport-equation

modified 1 hour ago EditPiAf 16k

0

votes

0

answers

20

views

What does it mean for this proposition to hold in $Top_*$?

algebraic-topology homotopy-theory stable-homotopy-theory

modified 1 hour ago Doron Grossman-Naples 63

0

votes

1

answer

20

views

How to prove uniform convergence of the integral?

functions convergence-divergence improper-integrals

modified 1 hour ago Quanto 36.3k

1

vote

0

answers

15

views

Set of lower dimension has Lebesgue measure zero?

real-analysis integration measure-theory lebesgue-integral lebesgue-measure

modified 1 hour ago user3750444 113

0

votes

1

answer

22

views

Taylor Expansion of Logarithm of Determinant near Identity for Non-Diagonalizable Matrix

linear-algebra reference-request taylor-expansion matrix-calculus matrix-analysis

modified 1 hour ago greg 15.4k

0

votes

0

answers

13

views

How many “linkage shapes” in the plane have n “joints”?

homotopy-theory classical-mechanics plane-geometry

modified 1 hour ago Ellis D Cooper 11

0

votes

0

answers

9

views

What is the physical interpretation of $u_x(0,t)$, $u_x(1,t)$ and a negative diffusivity constant in 1D Heat Equation on $(0,1)$?

partial-differential-equations boundary-value-problem heat-equation

modified 1 hour ago maths54321 21

5

votes

1

answer

61

views

Let $T:\textbf{R}^{n}\to\textbf{R}^{m}$ be a linear transformation. Show that there exists a number $M > 0$ such that $\|Tx\|\leq M\|x\|$.

linear-algebra solution-verification cauchy-schwarz-inequality

modified 1 hour ago EagerToLearn 1,320

0

votes

1

answer

18

views

Riemann integrable function on each compact

real-analysis riemann-integration

answered 1 hour ago EBO 301

2

votes

1

answer

31

views

Finding the no of V-shaped Permutations?

combinatorics permutations solution-verification

answered 1 hour ago Phicar 5,868

0

votes

0

answers

10

views

Is a normalized cosine similarity a Bregman divergence?

inner-product-space euclidean-domain

modified 1 hour ago Matt 1

0

votes

0

answers

8

views

Set of hyperplanes through the origin intersecting an affine variety

algebraic-geometry

modified 1 hour ago Manos 21.6k

4

votes

1

answer

241

views

Is the infinite product of $-1 \times -1 \times -1 \times\dots = -i$?

complex-analysis riemann-zeta infinite-product

modified 1 hour ago Gerben 361

0

votes

0

answers

7

views

Convergence speed of variance estimator

probability estimation

asked 1 hour ago infal 71

6

votes

1

answer

1k

views

calculating the volume of a room with a lopsided ceiling

volume

modified 1 hour ago Community♦ 1

0

votes

0

answers

18

views

Inverse of $f(x)=x^n(1-x)^k$

inverse inverse-function

asked 1 hour ago Boby 4,392

2

votes

0

answers

11

views

Upper bound on size of $r$-balls about a vertex

graph-theory algebraic-graph-theory graph-invariants

modified 1 hour ago eigenspace 21

1

vote

1

answer

16

views

catalan numbers - counting sequances with sum of 0

catalan-numbers

answered 1 hour ago Brian M. Scott 494k

1

vote

1

answer

13

views

Poisson Kernel and Fourier Series

real-analysis poissons-equation

answered 1 hour ago David C. Ullrich 74.6k

2

votes

0

answers

31

views

Question about topological hourglass

general-topology quotient-spaces

modified 1 hour ago warm_fish 581

1

vote

1

answer

7

views

Vector Components configuration

linear-algebra

answered 1 hour ago Eduude 298

1

vote

1

answer

9

views

growth of population- solving initial value problem

ordinary-differential-equations

answered 1 hour ago EditPiAf 16k

1

vote

0

answers

29

views

3-dimensional surface volumn of a 4-dimensional hyperellipsoid

integration analytic-geometry volume multiple-integral elliptic-integrals

modified 1 hour ago Miaplacidus 11

0

votes

0

answers

6

views

$\text{Log}(1-z) \in H^p(\mathbb{D})$ for all $0<p<\infty$

complex-analysis hardy-spaces

asked 2 hours ago Sebpar 57

1

vote

1

answer

13

views

Must function $f$ substitute in integral be injective on segment?

calculus integration definite-integrals

modified 2 hours ago J. W. Tanner 36.9k

1

vote

0

answers

16

views

Stalks of Plane Conic $C \cong \mathbb{P}^1$ are UFD

algebraic-geometry ring-theory commutative-algebra local-rings

asked 2 hours ago Rachmaninow98 332

0

votes

0

answers

8

views

Question concerning the proof in the parametrisation of $\hat{g}$-intertwiners.

modules representation-theory lie-algebras

modified 2 hours ago B. Pasternak 1,648

0

votes

0

answers

9

views

Same normal coordinates for two different Riemannian metrics

riemannian-geometry

asked 2 hours ago Studentmathever 109

0

votes

1

answer

21

views

Expectation of Stopping Time for a Brownian Motion with a drift

probability-theory stochastic-processes stochastic-calculus brownian-motion stopping-times

modified 2 hours ago MF14 304

0

votes

0

answers

9

views

Non Linear Activation functions in Neural Networks

machine-learning neural-networks

asked 2 hours ago Sathvik Swaminathan 320

2

votes

2

answers

32

views

Can you explain why the coordinates of this third point are rational numbers?

number-theory elementary-number-theory prime-numbers gcd-and-lcm pythagorean-triples

answered 2 hours ago Lubin 51.5k

4

votes

0

answers

31

views

Prove a conjecture, balls in boxes, n steps

conjectures

asked 2 hours ago thermomagnetic condensed boson 141

0

votes

0

answers

4

views

Question about finding the open set where the matrix is positive definite using the characteristic polynomial.

matrices eigenvalues-eigenvectors positive-definite characteristic-polynomial

asked 2 hours ago Vilde 21

0

votes

0

answers

10

views

Laplacian and eigenvectors relationship

graph-theory eigenvalues-eigenvectors spectral-theory algebraic-graph-theory spectral-graph-theory

asked 2 hours ago lakdee 21

10

votes

1

answer

327

views

How to solve this system of ODEs

ordinary-differential-equations analysis

modified 2 hours ago Nikos Bagis 4,488

1

vote

0

answers

14

views

Stochastic differential equation problem for $e^{2 \int W_t}$.

stochastic-processes stochastic-calculus stochastic-differential-equations

modified 2 hours ago openspace 4,989

0

votes

0

answers

6

views

Plotting the graph of some functions with an acceptable accuracy

functions polar-coordinates

asked 2 hours ago Charles Manson 39

0

votes

0

answers

5

views

Can impulses offset in time be added in wave propogation?

partial-differential-equations wave-equation

modified 2 hours ago SPRajagopal 408

2

votes

1

answer

25

views

Set Theoretic naming for a union property

elementary-set-theory terminology

modified 2 hours ago Asaf Karagila♦ 334k

2

votes

0

answers

31

views

Galois types, factorization 2

category-theory accessible-categories

modified 2 hours ago user122424 2,996

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