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0

votes

0

answers

15

views

Check if $X$ is completely metrizable

general-topology complete-spaces

modified 2 mins ago dsk62 155

1

vote

1

answer

30

views

For given mean $\mu$ of random variable X in [0,1], what is the probability distribution function $p(X)$ that makes $VAR(X)$ maximum?

probability probability-distributions optimization lagrange-multiplier variance

modified 3 mins ago Eric Wofsey 259k

0

votes

0

answers

2

views

Proving that $\operatorname{Ext}_{\mathbb{Z}_p[G]}(T,M)=0$ for the torsion $\mathbb{Z}_p$-submodule $T$ of a $\mathbb{Z}_p[G]$-module $M$.

group-theory modules group-cohomology

asked 3 mins ago Diego 2,739

2

votes

0

answers

13

views

Show that $ \operatorname{Hom}(K[s]/I, A)$ is isomorphic to Z(I;A)

abstract-algebra algebraic-geometry commutative-algebra

modified 4 mins ago Bernard 162k

0

votes

0

answers

11

views

Question regarding Stokes' theorem.

multivariable-calculus surface-integrals stokes-theorem

modified 4 mins ago Aaroh Gokhale 43

0

votes

0

answers

2

views

Can we always “locate” a transitive model inside some larger transitive model?

logic set-theory model-theory

asked 4 mins ago Noah Schweber 187k

2

votes

1

answer

28

views

Why notate the solution to steady-state heat equation as $2\Phi$?

partial-differential-equations physics heat-equation

modified 5 mins ago Jap88 415

0

votes

0

answers

18

views

Find in closed form.$\int_0^{\frac{\pi}{2}}\left(\frac{\ln(1+\cos(x))}{1+\sin^2(x)}\right)\cos(x)dx=?$

integration definite-integrals improper-integrals

modified 5 mins ago Bacha mohamed 21

0

votes

2

answers

14

views

Find the almost certain convergence of $(Y_n), \, n \geq 1$

probability convergence-divergence random-variables

modified 6 mins ago Kavi Rama Murthy 242k

0

votes

0

answers

5

views

Why the function is not suitable for binary classification (yes/no)

functions machine-learning binary logistic-regression

asked 7 mins ago Sean John 9

0

votes

0

answers

6

views

Problem with Bayes Theorem exercise

probability conditional-probability bayes-theorem

asked 8 mins ago Mike 1

0

votes

1

answer

5

views

Critical points and similar properties of solutions of nonlinear Volterra integral equations

functional-analysis integral-equations

answered 9 mins ago Eric Towers 57.2k

1

vote

1

answer

16

views

Second moment of Silverman kernel

integration definite-integrals density-function moment-problem

answered 9 mins ago dan_fulea 18.2k

1

vote

3

answers

21

views

Series evaluation: 2x^2 + 4x^4 + …

power-series

answered 10 mins ago Rob Arthan 35.3k

0

votes

0

answers

10

views

Borel algebra always strictly smaller than its completion?

measure-theory lebesgue-measure borel-sets measurable-sets

modified 10 mins ago Ramiro 10.4k

0

votes

0

answers

22

views

Any positive integer greater than $11$ is a nonnegative linear combination of $5$ and $4$.

number-theory

modified 10 mins ago user871124 47

0

votes

1

answer

40

views

How to find a polynomial that passes through a set of points (not just $1$)?

algebra-precalculus polynomials systems-of-equations roots

answered 11 mins ago William Elliot 16.2k

2

votes

1

answer

17

views

Given any digraph $D$ is the flip distance to an acyclic reorientation of $D$ equal to the minimum cardinality of an acyclic feedback-set of $D$?

combinatorics graph-theory linear-programming orientation

answered 14 mins ago Misha Lavrov 82.3k

0

votes

2

answers

9

views

Reduction of Order On Functions

ordinary-differential-equations solution-verification frobenius-method reduction-of-order-ode

modified 15 mins ago Satyendra 30.2k

0

votes

1

answer

6

views

Orthogonal projection over $Z=\overline{\text{span}\{e_k;k\in I\}}$

functional-analysis hilbert-spaces orthonormal

answered 16 mins ago Kavi Rama Murthy 242k

-1

votes

1

answer

25

views

Proving inequality that (problably) using AM-GM

inequality

modified 17 mins ago Mindlack 19.1k

0

votes

1

answer

24

views

Let $f:[0,\infty) \to [0,\infty)$ be increasing and satisfy $f(0)=0$ and $f(x)>0 \forall x>0$.

real-analysis functional-analysis functions derivatives metric-spaces

modified 17 mins ago gg2121 3

7

votes

1

answer

121

views

Finding all natural $x$, $y$, $z$ satisfying $7^x+1=3^y+5^z$

number-theory elementary-number-theory exponential-diophantine-equations

modified 19 mins ago Aqua 78.5k

-2

votes

0

answers

18

views

Let $y = \sqrt{4 + \sqrt{64 + \sqrt{5096+ …}}}$ and $\sqrt{4x^2 + \sqrt{16x^2 + \sqrt{64x^2 + …}}} = 11 .$ What is the value of $x + y$

algebra-precalculus

modified 19 mins ago valkedin 1

5

votes

0

answers

232

views

+150

What is $\frac{\det(\hat{\Sigma_0})}{\det(\hat{\Sigma})}$ in terms of $\hat{\mu_1}$, $\hat{\mu_2}$ and $\hat{\Sigma}$

matrices statistics determinant covariance maximum-likelihood

modified 24 mins ago Hyperplane 7,379

0

votes

0

answers

7

views

Relation between optimal solutions in the Dual formulation and optimal solutions to the original convex problem

convex-optimization lagrange-multiplier duality-theorems karush-kuhn-tucker

modified 25 mins ago ironX 2,169

4

votes

2

answers

52

views

Difficult Laplace inverse transform

inverse-laplace

modified 25 mins ago Svyatoslav 466

0

votes

0

answers

7

views

The trapezoid rule has been used to approximate $\int_{2.3}^{3.1}f(x)dx$, find the maximum absolute error

numerical-methods solution-verification error-function numerical-calculus error-propagation

asked 29 mins ago Segmentation fault 1,551

5

votes

2

answers

827

views

Image of a disconnected set is disconnected

general-topology examples-counterexamples connectedness

modified 29 mins ago Arctic Char 6,062

0

votes

1

answer

20

views

How can an annuity pay you so much money that, even if you live to 100, you can outlive your assets?

finance

answered 30 mins ago Arthur 173k

0

votes

1

answer

13

views

Find a particular solution of the next system

calculus integration matrices ordinary-differential-equations systems-of-equations

modified 30 mins ago mrsamy 5,008

0

votes

1

answer

14

views

Generating Euler Bricks

diophantine-equations pythagorean-triples

answered 31 mins ago garondal 268

1

vote

1

answer

21

views

Density of squared random variable

probability probability-theory probability-distributions density-function

modified 34 mins ago Arash 670

1

vote

2

answers

23

views

Change from differentiation wrt to matrix to wrt to inverse of matrix for symmetric matrices

derivatives matrix-calculus symmetric-matrices

modified 37 mins ago greg 19.9k

0

votes

0

answers

6

views

Summing from m to n with initial modifier from 0 to 1

algebra-precalculus summation

asked 39 mins ago Bronze 1

0

votes

1

answer

26

views

What is significance of the row space?

linear-algebra vector-spaces

answered 39 mins ago fedja 13.1k

0

votes

0

answers

20

views

Prove $(U_1 + U_2) \cap (U_2 + U_3) \cap (U_3 + U_1) = (U_1+U_2) \cap U_3 + (U_1 + U_3) \cap U_2$

linear-algebra vector-spaces

modified 41 mins ago jMdA 323

1

vote

0

answers

21

views

To which large cardinal property this inaccessible cardinal is equal?

set-theory large-cardinals

modified 42 mins ago Zuhair 2,451

1

vote

1

answer

22

views

Intuition behind optimzation problem of ridge regression?

statistics regression data-analysis regression-analysis regularization

modified 44 mins ago V. Vancak 13.6k

0

votes

0

answers

6

views

Construct a $G_\delta$ using a Lebesgue measurable function

measure-theory lebesgue-measure

asked 46 mins ago cciirrcclllee 386

0

votes

1

answer

9

views

How can incremental fees be infinity for the majority of fund managers who don't beat the market?

infinity

answered 46 mins ago David K 74.3k

0

votes

0

answers

7

views

Mix of first price and second price auction problem.

solution-verification game-theory nash-equilibrium

asked 51 mins ago openspace 5,856

0

votes

0

answers

12

views

Suppose $\{\vec{x}, \vec{y}\}$ is a basis for $R^{2}$ and $A$. Show $A$ is invertible.

linear-algebra solution-verification

modified 52 mins ago A. Radek Martinez 1,005

0

votes

0

answers

26

views

Gaussian Random matrix and PDFs of its elements

matrices probability-distributions normal-distribution random-matrices

modified 52 mins ago why_me 93

1

vote

0

answers

10

views

Quadratic integers proof verification

abstract-algebra ring-theory

asked 52 mins ago no lemon no melon 921

0

votes

1

answer

27

views

Degree of minimal polynomial when number of distinct eigenvalues are given

linear-algebra matrices eigenvalues-eigenvectors minimal-polynomials

answered 53 mins ago PseudoNeo 8,411

4

votes

1

answer

498

views

Atiyah-Macdonald, Problem 6 of Chapter 1

abstract-algebra ring-theory commutative-algebra

modified 55 mins ago user26857 42.7k

2

votes

0

answers

10

views

A group of order $150$ has at least $4$ conjugacy classes made by elements of order a power of $5$?

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

modified 1 hour ago F.inc 979

2

votes

0

answers

11

views

A free algebra that is not generic

universal-algebra

asked 1 hour ago user107952 8,826

0

votes

0

answers

6

views

Finiteness of the volume of $G(F) \backslash G(\mathbb A)$

algebraic-number-theory automorphic-forms adeles

asked 1 hour ago D_S 24.2k

0

votes

0

answers

5

views

What's “the incremental fee for active management as a percentage of the incremental risk-adjusted returns above the market index”?

finance

modified 1 hour ago Co Didact 15

0

votes

0

answers

5

views

Prove that $\sum_{-\infty}^{\infty}\frac{(a;q)_nt^n}{(b;q)_n}$ is an analytic funciton in $b$.

integer-partitions pochhammer-symbol

asked 1 hour ago Sorfosh 2,857

0

votes

1

answer

12

views

How to find attributes from a function in machine learning?

functions machine-learning

modified 1 hour ago Countour-Integral 103

0

votes

0

answers

10

views

Prove that the open ball B(a,r) is a subset of the interior of the closed ball C(a,r)

general-topology

asked 1 hour ago Christine 1

0

votes

0

answers

10

views

Airy-like equation with non-linear term

numerical-methods airy-functions

asked 1 hour ago anatoly 101

0

votes

0

answers

5

views

Checking whether a matrix is a permuted Toeplitz matrix

linear-algebra probability combinatorics

asked 1 hour ago newbie 1

0

votes

0

answers

13

views

Does someone have the full list of different ways to describe the derivate from the paper On proof and progress in mathematics?

calculus derivatives differential-geometry continuity

asked 1 hour ago Daan 1

0

votes

0

answers

8

views

Isogonality in a complete quadrilateral

geometry projective-geometry

asked 1 hour ago JJM 420

0

votes

1

answer

65

views

Dualizing module implies Cohen-Macaulay

abstract-algebra commutative-algebra homology-cohomology homological-algebra cohen-macaulay

modified 1 hour ago user26857 42.7k

0

votes

0

answers

6

views

Order statistics and Binomial relationship in a homogeneous Poisson process

stochastic-processes binomial-distribution poisson-process order-statistics

modified 1 hour ago nalen 28

0

votes

0

answers

5

views

saddle point of lagrange function (interpretation)

multivariable-calculus optimization nonlinear-optimization lagrange-multiplier

asked 1 hour ago Laura 313

0

votes

1

answer

23

views

What is “numerically exact approach”?

numerical-methods terminology numerical-calculus

modified 1 hour ago Shaun 27.4k

1

vote

0

answers

15

views

properties of Radon-Nikodym derivative

measure-theory radon-nikodym

asked 1 hour ago wvnika x 127

0

votes

0

answers

12

views

Solution of Integration

exponential-function

asked 1 hour ago Abbass NASSER 1

0

votes

0

answers

13

views

If $f(x,y)$ is $C^{\infty}$ in $x$ and $y$ respectively, can we say that $f$ is $C^{\infty}$ in $x$ and $y$ simultaneously?

differential

asked 1 hour ago able20 811

15

votes

0

answers

106

views

Does there exist a real function with following properties?

real-analysis calculus

modified 1 hour ago N.Quy 972

0

votes

0

answers

7

views

Continuous functions using first-order logic

first-order-logic predicate-logic

asked 1 hour ago math_fc 67

0

votes

0

answers

15

views

Cyclic covers, degree, torsion

algebraic-geometry complex-geometry vector-bundles

asked 1 hour ago KAL 11

0

votes

0

answers

10

views

Recommended material to understand a proof in a complex dynamics book( Carleson )

complex-analysis reference-request complex-dynamics

asked 1 hour ago Saba Tavdgiridze 71

1

vote

0

answers

24

views

Can we say that a limit exists at a discontinuity?

real-analysis analysis

asked 1 hour ago Peter 63

0

votes

1

answer

11

views

an other definition of adherent value for a sequence in a topological space

general-topology

answered 1 hour ago Henno Brandsma 185k

3

votes

1

answer

106

views

Lattices of projections

lattice-orders quantum-mechanics von-neumann-algebras

answered 1 hour ago Eric Wofsey 259k

0

votes

0

answers

23

views

Calculate $\int_{S}^{} \frac{r\cdot n}{r^{3}}dS $ where $S$ is a surface

integration surface-integrals

asked 1 hour ago Dr.Mathematics 101

0

votes

0

answers

12

views

I need to know if the second order differential equation shown has analytical solution

ordinary-differential-equations

asked 2 hours ago Facundo 11

7

votes

0

answers

59

views

The fair soup division and approximating numbers

polynomials approximation

modified 2 hours ago Alex Ravsky 75.7k

2

votes

2

answers

36

views

Bilinear Form and Rank Proof

linear-algebra bilinear-form

modified 2 hours ago mathcounterexamples.net 51.1k

0

votes

0

answers

12

views

Minimum distance travelled in order to reach a known maximum acceleration given a constant jerk value?

calculus physics

modified 2 hours ago mindTree 131

0

votes

0

answers

9

views

A random variables takes on values symbolized by x. If the variable is normal distributed with a mean of 1000 and a standard deviation of 100.

statistics

asked 2 hours ago Mian Hussnain Javed 1

3

votes

0

answers

24

views

The Virasoro algebra and its representations

reference-request lie-algebras kac-moody-algebras

modified 2 hours ago njlieta 427

0

votes

1

answer

26

views

Statements about elements in $\mathbb{C}$

linear-algebra matrices

answered 2 hours ago irene dovichi 99

-2

votes

0

answers

22

views

What are the odds.

probability

asked 2 hours ago user881123 11

4

votes

1

answer

27

views

Can $(X, \left \| \cdot \right \|_{T})$ being a Banach space imply $T$ as a closed operator?

functional-analysis banach-spaces

answered 2 hours ago Physical Mathematics 3,786

11

votes

0

answers

44

views

Does $\mathbb{R}^2$ Contain Uncountably Many Disjoint Copies of the Warsaw Circle?

general-topology geometric-topology plane-geometry plane-curves continuum-theory

modified 2 hours ago John Samples 1,261

2

votes

0

answers

24

views

Asymptotics or methods for this integral

integration definite-integrals asymptotics

modified 3 hours ago Turing 21.8k

3

votes

0

answers

44

views

Knot theory and creative writing?

general-topology knot-theory

asked 3 hours ago Andres Sanchez 31

0

votes

0

answers

10

views

Intuition for universal pair of unitaries and group $C^*$-algebra

operator-theory operator-algebras c-star-algebras

asked 3 hours ago chhro 1,780

1

vote

0

answers

15

views

Solving 2nd order ODE using a system of ODEs

ordinary-differential-equations systems-of-equations

asked 3 hours ago tehiga3101 11

5

votes

1

answer

174

views

If $x\geq 1$, then $x^{x^{\cos(x)}}\geq (1-\sqrt{x}+x)^{(x+1)^{\cos(x)}}$

trigonometry inequality logarithms exponential-function

modified 3 hours ago Eric Wofsey 259k

0

votes

0

answers

9

views

Suppose X is a nonnegative, integer-valued random variable with mean μ and variance σ 2 . Compute the following:

probability derivatives summation improper-integrals moment-generating-functions

asked 3 hours ago ericdarling 1

0

votes

1

answer

949

views

How to write an if condition in Linear Programming?

linear-programming mixed-integer-programming

modified 3 hours ago Community♦ 1

2

votes

0

answers

23

views

Product and quotient of smooth functions on $\mathbb{R}$

real-analysis smooth-functions

modified 3 hours ago Dima 1,735

2

votes

0

answers

15

views

Central extension of the Heisenberg Lie algebra

lie-algebras homology-cohomology

modified 3 hours ago Ettore 322

2

votes

0

answers

16

views

Vector valued linear differential equation

ordinary-differential-equations multivariable-calculus

modified 3 hours ago Mr. Fields 33

3

votes

0

answers

23

views

If $f_n$ continuous functions then uniform convergence of $\sum_{n=1}^{\infty}f_n$ implies continuity of limit function

real-analysis solution-verification sequence-of-function

asked 4 hours ago falamiw 147

5

votes

0

answers

32

views

p-adic numbers vs real numbers

p-adic-number-theory

asked 4 hours ago Bourama Toni 59

7

votes

0

answers

34

views

A question about S4 modal system

logic

modified 4 hours ago ferdinand 480

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