Skip to main content

Top Questions

1 vote
1 answer
24 views

Eigenvalues of $A+cd^T$ without determinants

4 votes
2 answers
88 views

Proof of the identity $\operatorname{Li}_{s+1}(z) = z\frac{(-1)^{s}}{s!}\int_{0}^{1}\frac{(\ln t)^s}{1-zt}\,\mathrm dt$ for $s=2$

3 votes
3 answers
91 views

Proving directly that, for scalene $\triangle ABC$, the bisector of $\angle A$ and perpendicular bisector of $BC$ meet at a point on the circumcircle

6 votes
2 answers
144 views

How to evaluate : ${\int_0^1\frac{x\ln \left(\frac{x}{2-x}\right)K(\sqrt{x})}{\sqrt{(2-x)^5}}\,\mathrm{d}x}$

0 votes
0 answers
11 views

Find all the subsets from a set $\{1,2,3,\cdots,n\}$, which contain only coprime numbers.

2 votes
3 answers
99 views

Evaluate $\int_0^3\sqrt\frac{x^3}{3-x}dx$.

3 votes
5 answers
98 views

Evaluate $I\left(n\right)=\int_{0}^{\infty}\frac{1}{\left(e^{x}+e^{-x}\right)^{n}}\,\mathrm dx$

2 votes
1 answer
26 views

What is the number of such circular arrangements?

1 vote
1 answer
104 views

Solve the diophantine equation involving floor function

13 votes
4 answers
1k views

Evaluate $\int_0^1{\frac{y}{\sqrt{y(1-y)}}dy}$

3 votes
1 answer
335 views

Non-Hamiltonian $k$-connected $k$-regular graphs ($k>3$)?

13 votes
3 answers
1k views

A Pell equation inside a Pell equation

1 vote
0 answers
18 views

Bound on $L^p$ distance for a Gamma distributed random variable

0 votes
1 answer
262 views

Exterior derivative characterization via generators?

13 votes
4 answers
1k views

Given triangle side lengths $a, b, c$, show that $3\left(a^2b(a-b)+b^2c(b-c)+c^2a(c-a)\right)\geq b\left(a+b-c\right)\left(a-c\right)\left(c-b\right)$

-1 votes
0 answers
94 views

On counting rational numbers

0 votes
2 answers
2k views

Find the Lipschitz constant for the following function

2 votes
2 answers
1k views

Generalization of Lipschitz continuity to higher order polynomials?

0 votes
0 answers
4 views

How write a mixed $L^p$ norm in the form of iterated $p$-integrals

90 votes
3 answers
8k views

Conjecture $\int_0^1\frac{\mathrm dx}{\sqrt{1-x}\ \sqrt[4]x\ \sqrt[4]{2-x\,\sqrt3}}\stackrel?=\frac{2\,\sqrt2}{3\,\sqrt[8]3}\pi$

4 votes
1 answer
92 views

How to prove that $\sum \limits_{k=1}^{n} \frac{(-1)^k}{k^2} \frac{\binom{2n}{n+k}}{\binom{2n}{n}} = -\frac{1}{2} \sum \limits_{k=1}^{n} k^{-2}$?

0 votes
0 answers
7 views

Jacobi Field Growth and Compactness under Sectional Curvature Bounds

5 votes
0 answers
304 views
+50

Extending the special function $G(n)=\prod_{k=1}^{n}k^{k^k}$ to any number

3 votes
2 answers
880 views

How many non-congruent triangles can be formed by the vertices of a regular polygon of $n$ sides

0 votes
0 answers
24 views

Ternary $1$-RLL encode decode with position-independent primer

0 votes
0 answers
23 views

Confusions about $\mathrm{Spec}(R)$ and algebraic groups

2 votes
0 answers
40 views

Cyclic sum of adjacent positive integers are power of 2

5 votes
1 answer
1k views

How to solve the eigenvalues of a complex matrix of very high condition number?

2 votes
1 answer
44 views

Bounds for derivatives of smooth function

0 votes
0 answers
24 views

Characterization of real numbers $ c $ for which $ \hat{\mu}(n) = e^{c i n^2}$ holds for a finite Borel measure $ \mu $ on $ \mathbb{T} $

1 vote
1 answer
171 views

A deceptive integral $\int{\frac{\sqrt{x-3}}{x+6}}dx$

1 vote
2 answers
52 views

Find $O(b)$ given that $a^5=e$ and $ab^{-1}a=b^2$

2 votes
2 answers
223 views

Points $A,B,C$ and $D$ are collinear. A point $P$ is such that $\cos\angle APC=\frac45$ and $\cos\angle BPD=\frac35$. What is $\sin2\angle BPC$?

3 votes
1 answer
116 views

Function spaces

3 votes
1 answer
302 views

What is the degree of the differential equarion $\sin\left(\frac{dy}{dx}\right)=x$?

1 vote
0 answers
22 views

Identity involving the polylogarithm and $\pi i/ 6$

3 votes
2 answers
152 views

Compute $\int_0^{\frac\pi2} \frac1{\sin(x+\frac\pi3)\sin(x+\frac\pi6)} dx$

6 votes
2 answers
305 views

Is there a direct derivation to show that $\int_0^\infty \frac{1-x(2-\sqrt x)}{1-x^3}dx$ vanishes?

9 votes
3 answers
240 views

If $\int_a^b\ln\left(\frac{3+3x+x^2}{1+x+x^2}\right)dx=0$, find the value of $2|a+b|$

2 votes
2 answers
1k views

Integral domain without unity has prime characteristic?

3 votes
1 answer
46 views

Exponential Rate Analog of Berry-Esseen.

3 votes
3 answers
693 views

Characteristic of a Non-unital Integral Ring

0 votes
2 answers
28 views

The order 4 isometry of the tetrahedron

2 votes
3 answers
592 views

In an equilateral triangle, lines are drawn from each vertex to the opposite side. Can there be seven regions of integer area?

2 votes
2 answers
111 views

Evaluate $\sum_{r=1}^{101}(-1)^{r-1}(1+\frac12+\frac13+...+\frac1r){101\choose r}$

0 votes
1 answer
1k views

Linear programming - Maximizing negative objective function

1 vote
1 answer
40 views

If $f_n$ converges locally uniformly to $f$ on open unit disc, does the difference quotient converge locally uniformly?

1 vote
2 answers
43 views

Can an arbitrary partition of the set of infinite binary words be seperated in the supremum by a function on the finite words?

3 votes
1 answer
17k views

Ice cream vendor problem

0 votes
0 answers
7 views

Question about singular matrix in thin-plate spline interpolation

13 votes
4 answers
40k views

Proof that Newton Raphson method has quadratic convergence

0 votes
0 answers
7 views

If $f(x) = \sum_{b \in B(x)}f_b(x)$ and $B(k) \subset B(k+1)$ while $\sum_{b \in B(k)} f_b(x) \geq \sum_{b \in B(k+1)} f_b(x)$ what is $f^{-1}(A)$?

1 vote
1 answer
132 views

Functions $\mathbb{N}\to\{0,1,2\}$ vs injections $\mathbb{N}\to\mathbb{Z}$

1 vote
1 answer
993 views

Transformation of continuous, independent random variables

0 votes
0 answers
7 views

Eigenvalues of $PA$ with $P$ a projection and $A$ having eigenvalues inside open unit disk

0 votes
1 answer
18 views

If ordinal $\alpha$ isomorphic to subset of ordinal $\beta$ then $\alpha \leq \beta$

2 votes
0 answers
20 views

Zeros of $f(z) = z^5 - ae^z$ in $B(0;1)$ for $a<0$

5 votes
3 answers
89 views

Does $L=\lim_{N\to\infty}N\int_{-N}^{N}\prod_{n=1}^{N}\cos\left(\sqrt{n}x\right)dx$ converge?

8 votes
2 answers
89 views

What [is the minimal] differential equation is satisfied by $y = \sum_{n=0}^\infty {x^n}(n!)^{-k}$?

4 votes
1 answer
73 views

What is the optimal geometry of a waffle?

5 votes
1 answer
144 views

Evaluate $\sum_{n=1}^{\infty} \left( \left(2n-1\right) \left(\frac{1}{n^2} + \frac{1}{(n+1)^2} + \ldots \right)^2 - \frac{2}{n} \right)$

0 votes
0 answers
12 views

Exact Triangle Sorting for Orthographic Rendering of a Triangulated Surface

0 votes
0 answers
32 views
+50

Can a symmetric bilinear form whose matrix representation is unitary be diagonalized wrt an orthogonal basis?

1 vote
0 answers
21 views

Evans' PDE: proof theorem 2 section 5.9

12 votes
1 answer
641 views
+100

Calculating $\int_0^1 \frac{\arctan^3(x) \log(x)} x\,\mathrm dx$

2 votes
2 answers
556 views

Prove that the length of the common chord is $\frac{2ab\sin \theta}{\sqrt{a^2+b^2+2ab\cos \theta}}$

3 votes
1 answer
211 views
+100

Wang–Chin partial order for comparing block matrix capacities

2 votes
1 answer
97 views

Approximate $\sec\left(\frac{\pi}{2}x\right)$ using $\frac{1-ax}{1-x}$

70 votes
2 answers
2k views
+250

Are the sums $\sum_{n=1}^{\infty} \frac{1}{(n!)^k}$ transcendental?

2 votes
1 answer
965 views

Semi filled barrel - pt 2

3 votes
2 answers
118 views
+50

Why is uniform convergence over $\omega$ not possible for sequences of random variables?

0 votes
0 answers
20 views

Null Space of Infinite Dimensional Matrix

-1 votes
0 answers
27 views

Negativity of a function involving the logarithmic functions

2 votes
2 answers
146 views

Is there a classification system where the sum of the digits are a factor?

0 votes
0 answers
30 views

$1/|x|$ interpreted as a distribution and Dirac delta distribution

2 votes
1 answer
84 views

Does the set $\{b^n - n \mid n \in \mathbb{N}\}$ always cover the complete residue system modulo a for any positive integers $a, b$?

0 votes
0 answers
25 views

given the following limit equality, prove the following statement

0 votes
1 answer
30 views

Examples of connected graphs that are hard to break (at least 3-connected) and have the following property

2 votes
1 answer
49 views

Probability (or asymptotics) that $G_{n, p}$ is a forest?

0 votes
0 answers
35 views

Computing $\pi_{n+1}(S^n)$ with Pontryagin's construction, why can we restrict to positive matrices?

0 votes
0 answers
17 views

Question on Einstein Notation for Distinct Expressions

2 votes
0 answers
26 views

A limit about a disk divided into strips and bars

1 vote
0 answers
22 views

Existence of a harmonic function with prescribed partial derivative in $\mathbb{R}^3$

2 votes
0 answers
51 views

An Inequality Conjecture in Harmonic Analysis

1 vote
0 answers
27 views

Deforming Contour in Method Of Steepest Descent

0 votes
0 answers
28 views

Recurrence relation between $n^{-1}$ and $(n+1)^{-1}$ in GF(p)

1 vote
1 answer
4k views

The advantage of B-spline compared to Bézier if the number of control points is very small

0 votes
0 answers
34 views

Finding the maximum of y in $\frac{x^a+1}{b^x}+\frac{x^b+2}{c^x}+\frac{x^c+3}{a^x}=y$ within a quadrant

12 votes
1 answer
8k views

How to find the degree of the differential equation $e^{y’}=y+x^5+x^3+x$?

1 vote
1 answer
168 views

Maximum radius of intersection of a plane and an ellipsoid

3 votes
2 answers
3k views

Find the points of the ellipsoid $x^2+2y^2+3z^2 = 1$ which are closest to and furthest from the plane $x+y+z=10$

0 votes
1 answer
108 views

Is every poset with this property already a lattice?

0 votes
1 answer
78 views

Is the derivative of $t^{1/2}\tanh(t^{1/2})$ is completely monotone on $(0,\infty)$?

3 votes
2 answers
971 views

A problem of permutations using the probabilistic method.

0 votes
0 answers
14 views

Analog to discriminant for ratio of polynomials and fractional powers of polynomials

0 votes
0 answers
35 views

f(x) bijections on modulo integer groups


Looking for more? Browse the complete list of questions, or popular tags. Help us answer unanswered questions.