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14

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extension of the Noether's Normalization lemma

algebraic-geometry commutative-algebra modules

modified 2 mins ago user26857 41.9k

0

votes

0

answers

5

views

On counting balls in an urn, combinatorics

combinatorics

asked 2 mins ago James 3,510

-2

votes

2

answers

15

views

Show that given conditional statement is a tautology by applying a chain of logical identities. $(p \land q) \rightarrow (p \rightarrow q)$

discrete-mathematics logic

modified 2 mins ago Khashayar Baghizadeh 760

0

votes

0

answers

4

views

Probability two uniform distribution(0,1) = 2/9

statistics self-learning

modified 1 min ago Michael Hardy 238k

0

votes

0

answers

6

views

Using Runge-Kutta integration to increase the speed and stability of gradient descent?

ordinary-differential-equations numerical-methods least-squares gradient-descent runge-kutta-methods

modified 3 mins ago Luke Hutchison 133

0

votes

0

answers

8

views

Extracting root of y^3=-x^2

analysis functions roots radicals absolute-value

asked 4 mins ago Andrew Carrol 1

3

votes

2

answers

77

views

Convergence of $\displaystyle\sum_{n=1}^{\infty}\frac{(2i)^{n}\cdot n!}{n^{n}}$

sequences-and-series complex-analysis convergence-divergence

modified 4 mins ago Bachamohamed 137

1

vote

2

answers

27

views

Question about Lim of derivative

calculus limits functions derivatives proof-explanation

answered 5 mins ago Mike 1,157

-1

votes

0

answers

15

views

Fundamental theorem of order - when are powers equal?

abstract-algebra group-theory

modified 5 mins ago user1787812 131

0

votes

2

answers

7

views

Number of ways to distribute 13 (out of 52) cards to 4 indistinguishable players.

combinatorics permutations

answered 6 mins ago YJT 1,253

0

votes

0

answers

7

views

Point lying on Jerabek Hyperbola

geometry triangles conic-sections triangle-centres

modified 52 secs ago A Z 75

0

votes

0

answers

9

views

bounded Cantor pairing?

functions cantor-set poker

modified 40 secs ago Bernard 152k

0

votes

0

answers

10

views

Analytic continuation of a function defined on a discrete set

complex-analysis analytic-continuation

modified 9 mins ago Sarah Mirth 31

1

vote

0

answers

19

views

Should $X$ be full column rank in normal Gauss Markov model to make $(\mathbf{y'y},\mathbf{X'y})$ be a complete statistic?

linear-algebra statistics statistical-inference regression parameter-estimation

modified 9 mins ago Facet 11

0

votes

0

answers

32

views

A question about the Collatz sequence

number-theory

modified 10 mins ago Pepperfogastre 27

0

votes

0

answers

32

views

How to solve summation convention

linear-algebra reference-request

modified 11 mins ago Meilton 23

3

votes

1

answer

17

views

Prove that biconditional cannot be expressed in terms of implication alone.

logic

answered 13 mins ago HallaSurvivor 6,286

2

votes

1

answer

35

views

Relation between tautological line bundle and blow up at the origin

geometry algebraic-geometry blowup

answered 14 mins ago Tabes Bridges 913

0

votes

0

answers

11

views

Give a cubic spline

numerical-methods

modified 14 mins ago Mohsen Shahriari 3,713

0

votes

0

answers

8

views

Solving a system of equations for all possible values of (x, y, z).

contest-math systems-of-equations

asked 17 mins ago fanzyee 1

0

votes

0

answers

2

views

Positive Quadratic Variation implies infinite total variation

reference-request brownian-motion quadratic-variation total-variation

asked 20 mins ago Andrew Shedlock 955

0

votes

1

answer

13

views

Distribution of the ratio of two Normal variables

statistics probability-distributions normal-distribution

modified 23 mins ago StubbornAtom 11.6k

1

vote

1

answer

22

views

How to make function that calculates the probability of two bugs will meet within $8$s timesteps?

probability logic

modified 25 mins ago Khashayar Baghizadeh 760

1

vote

0

answers

21

views

How to solve a Bernoulli ODE with an additional term?

ordinary-differential-equations partial-differential-equations

modified 26 mins ago BenG73 103

2

votes

2

answers

43

views

How can we find the pole of square root function?

complex-analysis roots

answered 26 mins ago paul garrett 35.9k

0

votes

1

answer

12

views

Modeling with differential and difference equations

ordinary-differential-equations recurrence-relations mathematical-modeling

modified 29 mins ago Yves Daoust 177k

0

votes

1

answer

12

views

Generalized remainder theorem for non linear factors

polynomials

answered 32 mins ago jaRedDRedmp 53

1

vote

0

answers

8

views

Finding largest delta value given epsilon for delta-epsilon limit

calculus limits epsilon-delta

asked 33 mins ago physicsaficionado 11

4

votes

1

answer

53

views

Book Request - General Relativity (for mathematicians)

differential-geometry reference-request book-recommendation general-relativity

answered 39 mins ago Taylor Rendon 833

3

votes

1

answer

91

views

Prime ideals in quadratic ring $\mathbb{Z}[\sqrt{-5}]$

ring-theory

modified 41 mins ago Maestro13 1,471

1

vote

1

answer

21

views

Prove that $m(\{x\in[0,1]:\lim \sup_{j\rightarrow\infty}f_j(x)\geq\frac{1}{2}\})\geq\frac{1}{2}$ under these conditions…

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

answered 43 mins ago Kenny Wong 22.5k

1

vote

0

answers

26

views

Consider the function $f(x) = x^2 + 2$ mod $17$. Use the two-pebble algorithm to determine the following parameters for starting point $x = 0$.

functions

modified 44 mins ago Khashayar Baghizadeh 760

0

votes

1

answer

17

views

Finding coefficients of a quadratic with roots having certain intervals

calculus

modified 44 mins ago Tavish 6,454

1

vote

1

answer

13

views

Identities with respect to composition

abstract-algebra category-theory morphism

modified 44 mins ago Berci 74.1k

-1

votes

0

answers

6

views

Product and Zeros of a function

infinite-product

asked 44 mins ago Daniel 103

0

votes

0

answers

17

views

$2\int_{0}^{\infty}\frac{\sin(s\tan^{-1}(x))}{(1+x^2)^{\frac{s}{2}}(e^{2x\pi}-1)}dx+\frac{1}{2}+\frac{1}{s-1}=\zeta(s)$

integration sequences-and-series improper-integrals riemann-zeta zeta-functions

asked 44 mins ago Bachamohamed 137

1

vote

2

answers

29

views

Integral in $3D$

real-analysis calculus integration continuity solution-verification

answered 45 mins ago RRL 68.3k

0

votes

0

answers

10

views

Restriction of an Exceptional Divisor $ E $ to itself is $ E^{2} = -H $ in $ E. $

algebraic-geometry

asked 45 mins ago AG Novice 405

0

votes

0

answers

6

views

Doesn't the simplex method work without artificial variables?

linear-programming simplex two-phase-simplex

asked 47 mins ago J R Smart 1

2

votes

0

answers

85

views

+500

Is there a simple-ish function for modeling seasonal changes to day/night duration and height of the sun?

functions trigonometry continuity mathematical-modeling

modified 47 mins ago Alexander Gruber♦ 26.4k

0

votes

1

answer

24

views

How do you find $P(C | A)$ and $P(C | A,B)$ of dependent events $A, B$, and $C$ given the following quantities?

probability conditional-probability

modified 49 mins ago Blue Eyed Daisy 955

0

votes

0

answers

40

views

Showing that $(\mathbb{C}[x,y]/(xy))_x\cong \mathbb{C}[x]_x$

abstract-algebra algebraic-geometry commutative-algebra localization

modified 50 mins ago user26857 41.9k

3

votes

0

answers

83

views

Interpretation of probability statements in Nina Zubrilina's paper

probability combinatorics graph-theory

modified 53 mins ago Michael Hardy 238k

0

votes

0

answers

5

views

Test for equality between two discrete distributions with lots of ties

statistics

asked 55 mins ago user3139990 23

1

vote

0

answers

20

views

Inscribing equilateral triangle in square — mistake in historical work by Abu'l-Wafa Al-Buzjani?

euclidean-geometry math-history

asked 58 mins ago Prime Mover 1,384

0

votes

1

answer

15

views

Show that $x < {n \over 1-P_x}$ where $P_x$ represents the CDF of gamma distribution.

probability probability-distributions gamma-distribution

modified 59 mins ago Fawkes4494d3 1,123

0

votes

3

answers

46

views

What is meant by a large subgroup?

group-theory algebraic-geometry algebraic-topology terminology definition

answered 59 mins ago JCAA 4,798

3

votes

0

answers

17

views

Does this orthogonal matrix parametrization have a name?

linear-algebra orthogonal-matrices

asked 1 hour ago Andrea Allais 81

2

votes

1

answer

28

views

Numerical quadrature for an improper multiple integral

numerical-methods improper-integrals mathematical-physics quadrature

modified 1 hour ago uranix 5,232

0

votes

1

answer

14

views

Matroid induced by a matrix where a circuit's nullspace is spanned by a non-negative vector

matroids

answered 1 hour ago Randy Marsh 708

0

votes

1

answer

18

views

Inverse Laplace transform of $\exp(-s)F(s)$

laplace-transform

modified 1 hour ago Sebastiano 2,102

0

votes

0

answers

4

views

Mode decomposition and eigenvalues of radial Schroedinger operators in N-dimensions

spectral-theory eigenfunctions minimal-surfaces

asked 1 hour ago user2020 1

1

vote

1

answer

21

views

Proof of Morera's Theorem for Triangular Contours

complex-analysis solution-verification contour-integration cauchy-integral-formula

answered 1 hour ago jaRedDRedmp 53

1

vote

0

answers

19

views

translation of a Jordan region

real-analysis calculus multivariable-calculus solution-verification volume

modified 1 hour ago Gord452 323

0

votes

0

answers

12

views

Average expected survival

probability

asked 1 hour ago Daniel says Reinstate Monica 1,113

-1

votes

1

answer

28

views

Multi-choice: ${A=\int_{\pi}^{3\pi}\frac{|\cos(x)+\sin(x)|}{x}dx}$ satisfies which inequality?

definite-integrals

modified 1 hour ago Riemann'sPointyNose 2,662

0

votes

1

answer

10

views

Linear law: how to determine three unknown constants from a non-linear equation?

algebra-precalculus systems-of-equations

modified 1 hour ago Kevin López Aquino 184

0

votes

0

answers

7

views

With Khinchine's inequality, prove Fourier basis is unconditional in $L^{p}[0,1]$ only for $p=2$.

banach-spaces harmonic-analysis schauder-basis

asked 1 hour ago Eric Yan 43

0

votes

0

answers

24

views

Question about probability terminology

probability probability-theory graph-theory terminology network

modified 1 hour ago RobPratt 13.8k

0

votes

0

answers

9

views

If the blow up module $B_{\cal J} M$ is finitely generated, why is $M_n \oplus M_{n+1} \oplus \cdots$ generated by $M_n$ as a $B_I R$-module?

abstract-algebra commutative-algebra graded-rings graded-modules

modified 1 hour ago Al Jebr 9,345

0

votes

1

answer

19

views

Linear system with outer product and inverted matrix

linear-algebra matrices systems-of-equations symmetric-matrices outer-product

modified 1 hour ago phil 81

2

votes

3

answers

67

views

What is the most direct proof of $f$ is continuous iff $f\left(\overline{A}\right) \subset \overline{f(A)}$?

general-topology continuity

modified 1 hour ago Henno Brandsma 169k

1

vote

1

answer

18

views

Second order derivative of a chain rule (regarding reduction to canonical form)

multivariable-calculus partial-differential-equations

modified 1 hour ago Jek Denys 79

0

votes

0

answers

16

views

Volume (or surface) of $d$-simplices ($d<n$) in $\mathbb{R}^n$

determinant volume simplex

modified 1 hour ago z32a7ul 105

0

votes

0

answers

15

views

Prove that for any $k$, $\forall x \, \, \, h(a+x)=h(a-x) \Longleftrightarrow \mu=0.5$

calculus definite-integrals symmetric-functions

asked 1 hour ago Masoud 2,335

2

votes

0

answers

19

views

Comparing the cardinalities of generic $\mathbb{R}$s

logic set-theory axiom-of-choice descriptive-set-theory forcing

modified 1 hour ago Noah Schweber 170k

1

vote

0

answers

20

views

Combinatorial interpretation of moments of usual law

combinatorics probability-theory probability-distributions

modified 1 hour ago JCAA 4,798

0

votes

0

answers

7

views

Maximality of an ideal implies co-maximality

abstract-algebra ring-theory

asked 1 hour ago Gitika 323

9

votes

0

answers

60

views

Proof a 'well-known' result of Shimura on periods of modular forms

reference-request p-adic-number-theory modular-forms l-functions

modified 1 hour ago Arbutus 1,779

0

votes

0

answers

13

views

level curve and convex function

real-analysis calculus

asked 1 hour ago Ken 592

0

votes

0

answers

20

views

How to express any irrational number in radicals as a trigonometric expression

trigonometry irrational-numbers

asked 1 hour ago outmind 135

2

votes

0

answers

14

views

Example of distinct Lie algebras with the same derivation algebra?

lie-algebras

modified 1 hour ago Dry Bones 21

0

votes

0

answers

20

views

Is $(a,b) \in \phi \equiv \phi(a,b)$?

elementary-set-theory logic notation terminology

asked 1 hour ago Taylor Rendon 833

0

votes

0

answers

9

views

How to determine the coefficient $c_m$ in $ \sum_m^{\infty}c_me^{-m\mu}\cos m\theta=\sinh (\mu-\mu_b)\cos\theta$ on some surface $\mu=\mu(\theta)$

numerical-methods fourier-analysis fourier-series

modified 2 hours ago Yolbarsop 11

0

votes

0

answers

27

views

Zeros of Riemann-Zeta function

number-theory

modified 2 hours ago Daniel 103

2

votes

0

answers

20

views

Can Definite integral get 2 answers due to the presence of square root?

integration definite-integrals roots

asked 2 hours ago ROBIN RAJ 329

7

votes

1

answer

809

views

Diffeomorphism invariance of the Ricci tensor

differential-geometry riemannian-geometry

answered 2 hours ago Prakhar Gupta 582

0

votes

0

answers

16

views

Conditional distributions being Gaussian implies joint distribution is also Gaussian?

probability statistics

asked 2 hours ago zhongyuan chen 525

-1

votes

0

answers

7

views

Simple Regression in statistics

regression

modified 2 hours ago Aryadeva 24.4k

0

votes

0

answers

5

views

segment whose ends are the points of intersection between the Euler line and the triangle

analytic-geometry

asked 2 hours ago Wilson Massaro 113

1

vote

1

answer

25

views

Primes, Digits, and Number Theory in Competition Math

number-theory

answered 2 hours ago Ross Millikan 340k

0

votes

0

answers

8

views

an $n$-gon is a jordan region

real-analysis calculus geometry multivariable-calculus solution-verification

modified 2 hours ago user3472 165

1

vote

0

answers

10

views

Subspace of $H^1(\Omega)$ is closed?

general-topology sobolev-spaces

asked 2 hours ago Raphaël 105

1

vote

0

answers

20

views

Is it possible to rewrite this proof in a more intuitive form?

proof-writing proof-explanation first-order-logic

asked 2 hours ago Patrick Browne 195

4

votes

4

answers

197

views

Four equilateral triangles in a rectangle

euclidean-geometry triangles area puzzle quadrilateral

modified 2 hours ago José Carlos Santos 280k

1

vote

0

answers

23

views

Katz's proof of Cartier's (descent) theorem

algebraic-geometry proof-explanation connections quasicoherent-sheaves positive-characteristic

asked 2 hours ago clarkkent 31

0

votes

0

answers

13

views

Show $\mathbb{E}[ t^{\sum_{j=1}^n \mathrm{1}_{\{v_i = j\}}Z_j}] = \frac{E[t^Z] - 1 + \eta} \eta $

probability probability-theory expected-value

modified 2 hours ago Michael Hardy 238k

1

vote

0

answers

11

views

Characterization of the continuity of a linear map $u:A \subset E \to F$ defined in a subspace $A$ of an $LF-$space $E$

functional-analysis continuity topological-vector-spaces

modified 2 hours ago Victor Hugo 1,141

2

votes

3

answers

71

views

How to solve $\int_0^1dx\int_0^1\frac{x^2-y^2}{(x^2+y^2)^2}\,dy$

calculus multivariable-calculus definite-integrals

modified 3 hours ago Michael Hardy 238k

0

votes

1

answer

13

views

You can prove that compacts in the weak topology are limited without the Eberlein-Šmulian theorem

functional-analysis weak-topology

answered 3 hours ago Nate Eldredge 79.7k

5

votes

3

answers

158

views

Given a matrix $A$ find $A^n$.

linear-algebra matrices

modified 3 hours ago José Carlos Santos 280k

0

votes

0

answers

7

views

From pointwise convergence in probability to uniform convergence in probability for non-decreasing random processes

convergence-divergence stochastic-processes

asked 3 hours ago Fabien 116

0

votes

1

answer

109

views

Infimum and supremum of $\int_{0}^{1} e^{x(t)}(x'(t))^{2} \; dt$

real-analysis ordinary-differential-equations calculus-of-variations

modified 3 hours ago Mike 45

1

vote

1

answer

31

views

Given $n$, what is the largest $m$ such that $m^2\prod_{i=1}^n(p_i-2)+\prod_{i=1}^n(p_i-1)\le \prod_{i=0}^np_i$?

combinatorics elementary-number-theory prime-numbers

answered 3 hours ago Daniel Fischer♦ 186k

1

vote

1

answer

53

views

Tricky lagrange optimization problem

geometry optimization lagrange-multiplier

modified 4 hours ago Cesareo 17.4k

3

votes

0

answers

12

views

Product of two functions in $H^1$( or $W^{1,2}$) is in $H^{\frac{1}{2}}$.

sobolev-spaces distribution-theory

asked 4 hours ago Lev Bahn 2,428

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