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0 votes
1 answer
7 views

Origin of a term in an inequality.

0 votes
1 answer
8 views

Almost Sure Convergence of a Random Variable

0 votes
0 answers
7 views

Why is "More Data Better than Less Data"?

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0 answers
4 views

When we calculate the irr, how to decide the initial range of irr?

1 vote
0 answers
5 views

Elementarily equivalent models of arithmetic that are not isomorphic.

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0 answers
18 views

Find the derivative of $\frac{d}{dx}\left(\tan \left(\sqrt{x}\right)\right)$ - no chain rule

0 votes
1 answer
905 views

Find the center of mass of a quarter circle given by $\sqrt{r^2−x^2}$, $x\in[0,r]$

0 votes
0 answers
30 views

Are there more real numbers in the interval $[1,\infty)$ than in the interval $(0,1]$? Or not?

0 votes
1 answer
21 views

Function class consisting of gradients of real-valued convex functions

0 votes
0 answers
13 views

What is the difference between the principal square root of $x$ and $x^{1/2}$?

0 votes
1 answer
21 views

For what values of $p>0$ is $\lim_{n\rightarrow\infty}\int_0^\infty\frac{(1-\frac{x}{n})^ne^x}{n^p}=0$?

0 votes
0 answers
5 views

Conditional distribution of one of the two exponential random variables, given one is smaller than the other

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1 answer
14 views

Pullback is not exact

0 votes
0 answers
4 views

Are we able to Compare the Fisher Information of Two Variables?

0 votes
0 answers
5 views

What are the conditions for cosets of a certain group to form a group themselves?

0 votes
0 answers
5 views

can we always get the variables of a system of linear equations given the system is valid?

3 votes
0 answers
24 views

Calculation on Riemannian manifolds

1 vote
0 answers
46 views

Prove that if $y \neq 0$ and $n$ is odd, then $x^n+y^n=(x+y)^n$ only if $x=0$ or $x=-y$ (Spivak's Calculus, Ch. 11)

0 votes
0 answers
6 views

Homology of the complement of a simple closed curve in a surface

2 votes
0 answers
16 views

The coupon collector's most collected coupon

3 votes
2 answers
105 views

Combinatorial interpretation of Euclid's form for even perfect numbers

0 votes
0 answers
12 views

Cardinal of a set (proof verification)

4 votes
1 answer
95 views

Why this partial function is not computable?

0 votes
0 answers
13 views

I cannot prove that $T$ is diagonalizable $\Rightarrow$ $T|_{V_1},T|_{V_2},\dots,T|_{V_r}$ are diagonalizable.

-1 votes
0 answers
13 views

consider the following relation on the set of positive integers.

1 vote
1 answer
11 views

Maximality of matching after contracting an odd cycle in a graph

0 votes
1 answer
17 views

$u$ be the sol of $\Delta u+ a_i(x)\frac{\partial u}{\partial x_i}= f(x)$ if $f\geq 0$ then u is constant and $f=0$

2 votes
0 answers
26 views

An interesting recurrent equality, possibly easier to solve in its differential form?

1 vote
0 answers
83 views
+50

Prove Kolmogorov's strong law of large numbers from Breiman ergodic theorem

6 votes
1 answer
3k views

Bayesian Interpretation for Ridge Regression and the Lasso

0 votes
1 answer
21 views

How to linearize a state space equation with higher order $>2$?

0 votes
0 answers
15 views

For a compactly supported, continuously differentiable function $f$, do we have $\frac{f(x+h)-f(x)}{h}\to f'(x)$ uniformly?

2 votes
0 answers
21 views

"Spanning" of solutions of ordinary differential equations

1 vote
0 answers
30 views

Help showing that two sets are equal.

1 vote
0 answers
15 views

Why does the following remark on probability space not work on infinite, yet countable, sets?

2 votes
1 answer
20 views

Proof of Wronskian relation using induction

1 vote
1 answer
6 views

Must a certain continuous map have 0 in its image, given that its restriction to the unit sphere is homotopic to the identity?

1 vote
1 answer
41 views

The derivative of a semialgebraic map is semialgebraic

6 votes
0 answers
45 views

Why does Galois theory most naturally take place in the context of fields?

3 votes
1 answer
32 views

On the number of roots of $p(z,\bar z)$

1 vote
0 answers
37 views

Proof from Lang’s Basic Mathematics

3 votes
1 answer
22 views

What do the elements of the chains of a simplicial complex represent?

1 vote
0 answers
18 views

Global Langlands for tori?

2 votes
0 answers
29 views

Is there a function $f$ from reals to reals such that every non-vertical line intersects $f$ infinitely many times?

1 vote
1 answer
13 views

Conditioning in Event Language VS Proposition Language

2 votes
0 answers
30 views

Why is $\int_{0}^{2\pi} \int_0^{2\pi} \frac{\ln(21-4(\cos x+\cos y+\cos(x+y)))}{2\ln(9/2)}\frac{dx}{2\pi} \frac{dy}{2\pi}$ almost $1$?

1 vote
1 answer
29 views

An inequality: from the complex to the real case.

0 votes
0 answers
32 views

How to proof this formula about Euler constant: $\gamma=\int_0^1\frac1{x+1}\sum\limits_{v=0}^\infty x^{2^v-1}dx$

1 vote
0 answers
10 views

Direct sum of small modules is small, also direct summands of small modules are small.

2 votes
1 answer
42 views

Solution verification of an approximation of an integral

3 votes
0 answers
32 views

What' s the asymptotic behaviour of this integral?

1 vote
0 answers
24 views

Determine if $f(x,y)=e^{-xy}\cos(2x)\cos(y)$ is integrable via Fubini

2 votes
0 answers
21 views

Calculating the angle between 2 one-sided surfaces.

1 vote
0 answers
11 views

Exemple where tower property of conditional expectation is NOT verify

1 vote
0 answers
12 views

Approximating an open set in measure with another open set whose boundary has zero measure

1 vote
0 answers
21 views

Quadratic Reciprocity as an Analytic Statement

0 votes
1 answer
24 views

Proof that markov chain equilibrium using Farkas' lemma

8 votes
0 answers
95 views

Collatz conjecture but with $n^2-1$ instead of $3n+1.$ Does the sequence starting with $13$ go to infinity?

0 votes
0 answers
26 views
+100

Boundedness of singular integral operator on normalized bump functions implies boundedness on Schwartz functions controlled by suitable seminorms

0 votes
1 answer
28 views

Find parameter p such that the points $ A(1,−1, 0), \ B(2 ,0 ,1), \ C(1, p, 3), \ D(2 , 2 p, 5)$ lie in the same plane.

1 vote
0 answers
27 views

Proof: $C^\infty[0,1]$ is dense in $L^2[0,1]$

0 votes
0 answers
9 views

What set of matrices $X,Y$ satisfy $X \circ Y = X P Y$ for at least one permutation matrix $P$?

0 votes
0 answers
15 views

How many integer values of $m\in[-20;22]$ are there such that the equation $\log_2(x^2+m+x\sqrt{x^2+4})=(2m-9)x-1+(1-2m)\sqrt{x^2+4}$ has a solution?

3 votes
1 answer
24 views

Are invertibly cobordant manifolds diffeomorphic

0 votes
0 answers
9 views

Find $\mathbb{E}[\hat{\alpha}]$. Suggest a new estimate $\check{\alpha}$ of $\alpha$ which is unbiased, such that $\mathbb{E}[\check{\alpha}]=a$

1 vote
0 answers
14 views

General form of rank $2$ tensor invaiant under certain rotations

0 votes
1 answer
11 views

Theorem of the Maximum for discrete sequences of constraint sets?

0 votes
0 answers
15 views

Goldbach Conjecture and Triangular Number

4 votes
0 answers
86 views
+200

Does Lipschitz-kind "non-scalar ODEs" and PDEs could stand having finite-duration solutions?

1 vote
0 answers
27 views

Hyperplane contains an inversible matrix

0 votes
0 answers
22 views

Prove that there exists $x$ such that $\lvert\det J\phi_x\rvert=1$

0 votes
0 answers
6 views

Help on this article of Centralizers of Groups

2 votes
0 answers
11 views

Can we calculate the opponent's hidden values in this statistical battle?

0 votes
0 answers
21 views

What conditions are required to guarantee that my matrix is skew-Hermitian?

0 votes
0 answers
15 views

Number of functions under some conditions

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0 answers
21 views

How to calculate functions that are being integrated?

0 votes
0 answers
8 views

Decomposing a big and nef divisor into ample + effective

0 votes
0 answers
19 views

properties of symmetric difference of two set$|\Omega_1 \cap \Omega_2| |x_{\Omega_1} - x_{\Omega_2}| \le C(R) |\Omega_1 \Delta \Omega_2|$

2 votes
0 answers
38 views

Find asymptotic variance of moment estimator

0 votes
1 answer
18 views

Question about matrices and rref

-1 votes
1 answer
24 views

Prove that $|f'(x_0;e)| \leq 1$ for all direction $e \in \mathbb{R}^d$ with $||e||=1$

0 votes
0 answers
4 views

Using multivector residue theorem to evaluate multiple integrals

1 vote
0 answers
23 views

Decomposition of order 3 tensor symmetric along two dimensions

4 votes
2 answers
134 views

Periodic sequences of integers generated by $a_{n+1}=\operatorname{rad}(a_{n})+\operatorname{rad}(a_{n-1})$

3 votes
0 answers
9 views

Divisibility of unitriangular matrices over a field of characteristic 0

1 vote
1 answer
45 views

Find the cheapest arrangement of non-overlapping colored rectangles necessary to achieve a sequence of colors behind holes

1 vote
0 answers
8 views

Embedded arcs staying embedded after squaring.

0 votes
0 answers
18 views

Inequality with reciprocals of multi-indexes

0 votes
0 answers
15 views

Unconstrained minimizer as a linear combination

3 votes
0 answers
18 views

How to make sense of SDE notation

0 votes
0 answers
28 views

What's the probability that the numbers on the license plate of a random car add up to 21?

0 votes
1 answer
1k views

Residual analysis in Python

5 votes
0 answers
51 views

Master Tail Bounds Theorem Intuition & Perspectives

0 votes
0 answers
30 views

Let $f:\Bbb N^2\to\Bbb R:(m,n)\mapsto a^mb^n$, with $0<a<1<b$. Is $\operatorname{im}\! f$ dense in $\Bbb R_{>0}$?

1 vote
1 answer
64 views

Determinant of matrix with binomial coefficient elements equal to $\binom{2n-1}{n}$

1 vote
4 answers
55 views

What is the right adjoint to the functor $\sf{Psh}\to\sf{Set}$ which evaluates the presheaf on the whole space?

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