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Top Questions

0 votes
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2 views

stability of a numercial scheme for a hyperbolic system?

0 votes
0 answers
2 views

Is there any research about a function with changing "period" like sin(1/x)?

0 votes
1 answer
22 views

Quotient of $GL(\mathbb{R}^n)$ by $O(\mathbb{R}^n)$

1 vote
0 answers
30 views

Gershgorin discs Theorem

6 votes
2 answers
1k views

Inclusion/exclusion, at least and exactly arrangements?

2 votes
1 answer
48 views

Multiplying by $1$ adds a solution to an equation

3 votes
2 answers
87 views
+50

Find connected closed subgroup of $(\mathbb C,+)$

1 vote
0 answers
6 views

Can someone help find methods to study the asymptotic behavior of these integrals as $\rho \to \infty$?

3 votes
3 answers
33 views

Prove that $\lim\limits_{(x,y) \to (0,0)} \frac{xy(x-y)}{x^3 + y^3}$ does not exist

1 vote
0 answers
16 views

One sided Lipschitz condition

0 votes
1 answer
7 views

How do I translate this pattern of sentence into a quantified statement using logical operators?

4 votes
1 answer
40 views

how to show an inequality from P.D.E

1 vote
0 answers
19 views

Exercise 7(c), Section 31 of Munkres’ Topology

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4 views

section of locally free sheaf locally represent a tuple of functions

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0 answers
18 views

Matrix Inversion of $f(X) = (X^{-1}-A)$

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6 views

Likelihood of censored exponential random variables

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0 answers
4 views

Explore stationarity and continuity for $X(t) = W^2(t)-t$

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0 answers
6 views

Problem with intuition regarding sigma algebras and information

0 votes
1 answer
19 views

Does a combination of linearly independent vectors have a minimal value?

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0 answers
6 views

Product of conditional and marginal density for normal random variable densities

0 votes
1 answer
11 views

How do I normalize a vector such that the sum of its squared elements is some arbitrary c?

-2 votes
0 answers
22 views

Linear transformation and basis with euler

2 votes
1 answer
56 views
+50

making basis for a vector space from bases for subspaces

0 votes
1 answer
28 views

Why is $\lim_{x\to1}f(x)g(x+1)$ undefined, where $f(x)=2$ if $x=1$, $f(x)=\cos(\pi x/2)$ if $x\neq1$, $g(x)=1$ if $x<2$, and $g(x)=-1$ if $x\geq2$?

0 votes
0 answers
7 views

How do I prove $F_*Z=(Z^i\circ F^{-1})\partial_i'$, where Z is a field, and $(F(U),x\circ F^{-1})$ a chart with coordinate fields $\partial_i'$?

1 vote
0 answers
9 views

Solving integral with generic pdf

3 votes
2 answers
30 views

A circle, two tangents and a triangle - finding incircle center of triangle

0 votes
0 answers
19 views

An example showing that a quotient space of an hausdorff space is not hausdorff.

-1 votes
0 answers
8 views

Using polar coordinates transform double integral into integral of function from one variable. ${\int\int}_{(D)} f(\sqrt{x^2+y^2})dxdy$

3 votes
0 answers
57 views
+50

Using matrix to analyze an ODE system $\begin{cases}\dot a_k(t)=2(b_k^2-b_{k-1}^2)\\\dot b_k(t)=b_k(a_{k+1}-a_{k})\end{cases}$ with $b_0(t)=b_n(t)=0$.

0 votes
1 answer
2k views

Is the objective function $\max \min(f(x))$ convex for all $f(x)$?

0 votes
0 answers
14 views

non isomorphic algebraically closed fields

0 votes
0 answers
12 views

Block matrices in MATLAB.

3 votes
0 answers
15 views

Is $(1+c^2)^n-\lfloor(1+c^2)^{n/2}\rfloor^2<(1+c^2)^{(n+1)/2}$ true for all integers $c>1$, when $n$ is an odd integer?

0 votes
1 answer
17 views

What conditions does positive semidefiniteness impose on the matrix elements?

0 votes
0 answers
14 views

Which repeated shape covers a circle most efficiently

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0 answers
8 views

Confusion about branches in exponents

0 votes
0 answers
12 views

How can I calculate the computational complexity of an equation composed of $2n$ multiplications and $2nm^2$ additions?

0 votes
0 answers
16 views

Probability Algebra With a Wordle Example

3 votes
1 answer
29 views

If $f \in C^1(\mathbb{R}, \mathbb{R})$ and $|f(x)| + |x||f'(x)| \to 0$ as $|x| \to \infty$, do we have $f'(x) \in L^1(\mathbb{R})$?

1 vote
1 answer
9 views

A function of class $\mathcal{C^k}$ implies that all partial derivatives of order k-1 are continuous?

0 votes
0 answers
10 views

Show that $d(n^2+1)$ doesn't become monotonic from some point onwards

0 votes
0 answers
20 views

Remarquable identities $f(n) = \frac{a^n}{(a-b)(a-c)} + \frac{b^n}{(b-a)(b-c)} + \frac{c^n}{(c-a)(c-b)}$

2 votes
0 answers
78 views
+50

Plotting tight bounds for simple Wiener Brownian motion - problems with classic definitions

0 votes
0 answers
24 views

Difference of modified Bessel functions in integral form

1 vote
0 answers
36 views

Proving $|\inf f(x) -\inf g(x)| \le \inf| f(x) -g(x)|$

0 votes
1 answer
17 views

How to see that 'two manifolds are diffeomorphic when you can give them each a coordinate atlas with the same transition maps'

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0 answers
14 views

Prove by determinant properties

2 votes
0 answers
39 views

Is $d(f(x))=xf'(x)/f(x)$ a useful indicator of the growth of a function?

3 votes
1 answer
24 views

in the unit circle, names of the various points depending on the angle at the origin

1 vote
1 answer
20 views

How to derive the following estimate from example 3.9 in Bruce Palka's textbook: $|\int_\beta\frac{e^{iz}}{z}\,dz| \leq \frac{\pi(1-e^{-r})}{r}$

1 vote
0 answers
14 views

Unsure about Conditional Probability question

0 votes
0 answers
5 views

How can I that if $part(G'[A]) = part(G'[B])$, then $part(G[A]) = part(G[B])$

1 vote
1 answer
22 views

Computing areas using Green's theorem

3 votes
1 answer
45 views

Do any two structures of a language with constants have a common non-trivial substructure?

5 votes
1 answer
161 views
+50

How to show $\frac{1}{\delta} \mathbb{P}[ \sup_{t\leq s \leq t+\delta} |X(s)-X(t)|\geq \epsilon] \leq \eta$?

1 vote
0 answers
48 views
+200

What is the $t$-anti-derivative $\int dt \; e^{i t}\mathrm{Ei}\big(- i [t+x]\big)\; t^{-n}$ for $n = 1,2,3$?

1 vote
0 answers
14 views

Gershgorin circle theorem matrix condition

3 votes
0 answers
40 views

How did Lanczos find his approximation for the Gamma function?

0 votes
0 answers
7 views

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

0 votes
0 answers
36 views

check that the unit disk of $\Bbb C$ is a subset of union of circles

1 vote
1 answer
12 views

Conjecture about chordal graphs

1 vote
0 answers
12 views

How do I solve this nonlinear ODE given the asymptotic series solutions as follows?

0 votes
2 answers
34 views

Is the error function and $\mathcal{N}(0,1)$ the same thing?

1 vote
1 answer
18 views

Does $f:X \longrightarrow Y$ open, continuous and surjective preserve being $T_0$?

0 votes
0 answers
8 views

Some question about $\ell_p$ and metric $d_p$ with $p\in (0,1)$

4 votes
0 answers
171 views

Dimension of a constructible set intersecting each orbit of a $G$-variety

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6 views

Estimation of operator norm of the difference between identity and Gram matrix?

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13 views

What does it mean that a function is unbounded below in every neighborhood?

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12 views

Spivak's Calculus: Understanding proof of alternative form of l'Hôpital's Rule

2 votes
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24 views

Showing integrability of random variable at stopping time

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0 answers
19 views

Grassmann Algebra - Show that the integral operator is equal to the derivative operator up to a constant.

0 votes
1 answer
26 views

why $|a|=|\sigma (a)|$, where $|\cdot|$ denotes absolute value on $\overline{ \Bbb Q_p}$?

1 vote
0 answers
13 views

A conditional negative definite quadratic form involving $\ln$ function

0 votes
0 answers
10 views

Proving that $d((x_n),(y_n)) := 2 ^{−\min \{n \in \mathbb{N}: x_n \neq y_n \} }$ defines a metric on $S$, $S$ being the set of $0-1$ sequence..

1 vote
0 answers
16 views

Subsets of indecomposable modules

2 votes
1 answer
204 views

What is the algorithm for performing continued fraction arithmetic

0 votes
0 answers
12 views

Continuity of correlation function

2 votes
1 answer
27 views

solve the pde without any initial condition $xu_x-xyu_y=u$

1 vote
0 answers
19 views

Showing that every smooth embedded Torus has a point with negative curvature

3 votes
0 answers
53 views

Return of Brownian motion to zero

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0 answers
9 views

Calculate stopping time based on force acting against object.

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0 answers
8 views

Image of annulus under flow of vector field and differential equations

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0 answers
11 views

Danskins's theorem for non-continuous variable

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3 views

Ensure continuity on the first-order derivative while minimizing functional

1 vote
0 answers
19 views

Induced group action on tangent bundle commutes with structure group?

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0 answers
11 views

Cohomology of matrix groups acting on vector spaces under change of basis

1 vote
3 answers
50 views

How to use exponential generating functions to count the number of k-letter permutations from n letters?

0 votes
1 answer
49 views

Is $K_t :\mathbb{T}\to\mathbb{C}, s\mapsto\sum_{n∈\mathbb{Z}}e^{-n^2 t}e^{ins}$ a summability kernel for $t\to 0^+$?

0 votes
1 answer
29 views

Using polar coordinates find area of $(x^2+y^2)^3=x^4+y^4$

1 vote
0 answers
14 views

Understanding Rokhlin's theorem of cross-sections

2 votes
2 answers
187 views

Reference request on Associative Algebras

1 vote
0 answers
8 views

Show that is continuous and coercive

2 votes
0 answers
12 views

Decomposition of a 4D rotation into a $\textit{particular}$ sequence of simple rotations.

1 vote
0 answers
7 views

Is the second moment of empirical spectral distribution of a Gaussian matrix uniformly bounded

2 votes
0 answers
9 views

When is the Haar measure of a centre strictly positive?


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