Skip to main content

Explore our questions

2 votes
1 answer
65 views

Understanding Achim Klenke's Probability Theory, Proof of Theorem 15.34

3 votes
4 answers
4k views

How to change the sign of the Dirac delta function argument?

6 votes
0 answers
91 views
+300

Specific invariants for cyclic groups in Galois theory

1 vote
1 answer
50 views

Help computing two regions for multivariable calculus

0 votes
0 answers
16 views

How to find $L=\prod\limits_{n\ge1}\frac{(\pi/2)\arctan(n) }{\arctan(2n) \arctan(2n-1) }$?

0 votes
1 answer
35 views

Finding rotations transform

0 votes
0 answers
7 views

LDL decomposition when D has different size

3 votes
1 answer
71 views

Question such that heuristics suggest $f(n) \mid g(n)$ infinitely but $f(n) \nmid g(n)$ for all $n \in \mathbb{N}$

0 votes
1 answer
21 views

Justifying $ y \cdot f\left(a \right) = (x) \cdot f\left(A \right) \cdot (\alpha)$ for $a\in R$ integral, $C \subseteq R$ integral domain extension

0 votes
0 answers
21 views

Triangle center dividing it in three quadrilaterals of the same area

1 vote
4 answers
49 views

Is there a "natural" example of a poset that is not a lattice?

3 votes
1 answer
116 views

Divide a right triangle into three quadrilaterals of equal area .

0 votes
0 answers
17 views

Non orientability of a manifold

0 votes
1 answer
23 views

Prediction of term asymtotic from sum asymtotic.

2 votes
2 answers
764 views

Show by left coset action that if $H$ is proper subgroup of $A_5$, then $[G:H]>4$

0 votes
1 answer
48 views

clarification about second derivative test on the real functions

2 votes
1 answer
55 views

Bounding the difference between the ground state energy of a Hamiltonian and the expectation of the Hamiltonian

1 vote
2 answers
758 views

Prove row space of RREF equals row space of matrix

15 votes
12 answers
843 views
+200

Seeking different ways you can find $x=8$ in $(x-6)^3 = x^{\frac{1}{3}}+6$

3 votes
1 answer
32 views

Probability of random 5-degree polynomial has double integer roots (1,1)

4 votes
1 answer
93 views

Does uniform convergence on compact subsets of $\mathbb{R}$ imply weak convergence in $L_p(\mathbb{R})$?

3 votes
1 answer
154 views

Does anything deeper hide behind this inequality?

0 votes
0 answers
7 views

Convergence in distribution to stationary SDE solution

-1 votes
1 answer
107 views

How do I check whether $\mathbb{Q}[x]/(x^3+2)$ is a field without using the irreducibility criterion?

2 votes
2 answers
47 views

Erdős Problem 943 (and its Lean formalisation)

21 votes
3 answers
450 views

Does $\sum_{n=0}^{\infty}\frac{(4n)!^2}{2^{8n}(n+1)^2(2n)!^4}$ has the proposed closed form?

2 votes
0 answers
56 views

How to recover an affine group scheme

1 vote
1 answer
101 views
+50

Understanding distributions in "An Introduction to Quantum Field Theory" by George Sterman

5 votes
1 answer
312 views

Prove $\frac{a^2}{b} + \frac{b^2}{c} + \frac{c^2}{d} + \frac{d^2}{a} \ge \sqrt{4(p^2 - 2q) + 8\left(p^2 - \frac83q\right)}$

2 votes
1 answer
52 views

A contest problem about Tic-Tac-Toe

20 votes
4 answers
47k views

Is the relation $R = \emptyset$ reflexive, symmetric and transitive ? Why?

2 votes
3 answers
152 views

Probability question on drawing balls

-1 votes
1 answer
37 views

prove this sequence is absolutely p-summable

20 votes
1 answer
980 views

Exercise I.3.19 in Hartshorne — still an open problem?

0 votes
1 answer
19 views

Length of submodules in a cyclic uniserial module

2 votes
1 answer
39 views

Lebesgue measure on $\mathbb{R}^d$ as a tempered distribution

0 votes
0 answers
11 views

Hypothesis testing with a sample from a shifted exponential distribution (Jun Shao - Mathematical Statistics, exercise 6.20, point (v))

0 votes
0 answers
25 views

Relation between cuts of ellipsoid by lines and the ellipsoid itself

4 votes
1 answer
747 views

Prove that $N(Z;Y)$ is trivial if and only if there exists a set of $k$ independent functions $g_1,…,g_k$ for $Z$ on some set $U$ in $Y$.

2 votes
1 answer
54 views

How to find Farkas certificates?

0 votes
2 answers
754 views

An Efficient Minimum Distance Bipartite Matching Algorithm

0 votes
1 answer
66 views

Does the iteration of the function $N=2^{k+1}\cdot m-1$ , (where $m=\frac{2^{t}\cdot n+1}{3^{k+1}}$) eventually produce all odd multiples of 3?

0 votes
1 answer
55 views

Regarding equivalent statements of Structure Theorem for finitely generated modules over PIDs

0 votes
0 answers
12 views

is there software that can generate graphs from sets of points for Euclidean graph theory?

12 votes
3 answers
15k views

Calculating SVD by hand: resolving sign ambiguities in the range vectors.

3 votes
1 answer
102 views

Relative singular homology of the pair $(\mathbb{R},\mathbb{R}-\{0\})$

0 votes
2 answers
39 views

Showing that the covariance matrix between these two variables is diagonal.

45 votes
3 answers
42k views

Name for diagonals of a matrix

1 vote
0 answers
24 views

Problem 3 of part b of 4.5.1 of Evans' PDE

1 vote
0 answers
20 views

Farb & Dennis Corollary to Nakayama's Lemma: When surjectivity modulo J(R) implies surjectivity

1 vote
1 answer
159 views

Replace a random variable by a "small" Gaussian

1 vote
1 answer
78 views

Fractional states for the quantum harmonic oscillator

0 votes
0 answers
15 views

Problem 2 of part b of 4.5.1 of Evans' PDE

2 votes
1 answer
93 views

Is this set of Diophantine equations independent?

21 votes
4 answers
867 views
+100

Six circles in a rectangle: show that two lengths are equal

0 votes
0 answers
31 views

Problem 1 of part b of 4.5.1 of Evans' PDE

7 votes
3 answers
2k views

If ${a}$ is an arbitrary integer, then prove that ${360|a^2(a^2-1)(a^2-4)}$.

11 votes
3 answers
59k views

Difference between PEMDAS and BODMAS.

2 votes
0 answers
59 views

$\sum_{j=2}^n\sum_{p=n}^\infty \frac1{p j^p} + \sum_{j=n+1}^\infty \sum_{p=2}^\infty \frac1{p j^p}<\frac1n$ for all $n\ge3$.

4 votes
3 answers
318 views

Evaluation of $\int_{0}^{1}\frac{1}{\sqrt{1+x}+\sqrt{1-x}+2}dx$

17 votes
2 answers
530 views

Help with $\int_{0}^{\pi /4} x^3 (\sqrt{\tan (x)} + \sqrt{\cot (x)}) dx$

0 votes
0 answers
20 views

How to round the corner between a line and a quadratic Bézier curve

0 votes
1 answer
749 views

Most accurate mean for grouped/ranged data

1 vote
1 answer
71 views

If $P\in\mathbb{R}[X]$ has simple real roots, then for $a\in\mathbb{R}^*$, the polynomial $P^2+a^2$ has only simple roots in $\mathbb{C}[X]$.

7 votes
3 answers
229 views

Cubic equation for closest point to a function

1 vote
0 answers
28 views

How far can an infinite number of unit length planks bridge an obtuse-angled gap?

6 votes
5 answers
9k views

What is the meaning of "independent events " and how can we logically conclude independence of two events in probability?

6 votes
3 answers
176 views

Connected components on a regular manifold

3 votes
2 answers
683 views

Dartboard paradox and understanding independence

4 votes
2 answers
975 views

Riemann Zeta Function?

0 votes
1 answer
16 views

Construction of a totally positive set in Hahn decomposition theorem

0 votes
0 answers
148 views

What known formulas are there that yield sequences with no known non-trivial cycles?

2 votes
1 answer
28 views

Caro Wei bound with second neighbors in triangle free graphs

0 votes
3 answers
176 views

Problem with my approach to "breaking a stick at two points"

6 votes
2 answers
692 views

Name of the algebraic structure

1 vote
1 answer
64 views

Number of Solutions to $x^2 - y^2 \equiv 2^r \ell \pmod {2^q} $

6 votes
1 answer
61 views

Does every Moore closure operator that satisfies $cl(\emptyset)=\emptyset$ arise as an intersection of Kuratowski closure operators?

5 votes
1 answer
247 views
+100

Is the ultrafilter lemma over $\omega$ enough for Banach-Tarski?

12 votes
3 answers
604 views

Die dilemma: get paid the sum or go home

2 votes
1 answer
765 views

Unfair Coin Toss

3 votes
1 answer
74 views

What is the shortest way to write an equivalent relation between n number of elements assuming that the transitive property is invalid.

3 votes
1 answer
758 views

Hartman-Grobman Theorem - Necessary?

3 votes
1 answer
784 views

"Functional example" of Cauchy sequence which is not convergent

2 votes
0 answers
103 views

Some examples of distributions of real random variables ( Achim Klenke, Probability Theory )

5 votes
0 answers
121 views

How many points are needed to cover a whole lattice?

4 votes
0 answers
98 views
+250

Over $\mathbb R^2$, given a tool that can $n$-sect an angle for any $n$, for which $n$ can you construct the $n$th root of any given $x > 0$?

0 votes
0 answers
16 views

Obtaining One of Multiple Subsets Coupon Collector Variant

4 votes
0 answers
67 views

The role of the de Rham theorem in $\nabla C^\infty(X)\cong C^\infty_0(X)$

2 votes
1 answer
106 views

Showing that a ring is Cohen-Macaulay

32 votes
6 answers
7k views

How to evaluate $\int_{0}^{2\pi}e^{\cos \theta}\cos( \sin \theta) d\theta$?

2 votes
1 answer
64 views

Are there infinitely many odd composite numbers with digit-disjoint factorizations?

0 votes
1 answer
41 views

Showing positive definite quadratic forms give the "most symmetrical" metrics over $\mathbb{R}^n$

0 votes
1 answer
925 views

Prove that if $f$ is Riemann integrable on $[0,1]$, then $f$ is measurable and it equals to Lebesgue integral.

3 votes
1 answer
111 views

The number of strings with bounded partial sums

2 votes
2 answers
70 views

Finding $CB$ given $BC=A(B−A)^{-1}$ for non-singular matrices

0 votes
1 answer
762 views

Relation between autocorrelation and mean of a stochastic process

Browse more Questions