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0

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4

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What is the distribution of the dot product of a flat Dirichlet vector with a fixed vector?

probability simplex

asked 3 mins ago nerya 1

0

votes

0

answers

8

views

Double product of 2^i*3^j

products

asked 4 mins ago Skyler H 11

1

vote

2

answers

45

views

Solve $\int_{1}^{x} \frac{dt}{f'(t)+3} = \frac{1}{x} + x^2 -2$ for $f(x)$

calculus integration ordinary-differential-equations derivatives

answered 4 mins ago Moko19 1,777

0

votes

0

answers

11

views

Find a certain decomposition of $\mathbb{C}S_3$

abstract-algebra representation-theory characters

modified 4 mins ago CoffeeArabica 1,267

1

vote

0

answers

26

views

Relation between Hochschild cohomologoy $HH^{n}(\mathbb{Z}[G], M)$ and the cohomology group $H^{n}(G,M)$ for $G$ a cyclic group

homological-algebra group-cohomology

modified 5 mins ago José Luis Camarillo Nava 775

0

votes

0

answers

4

views

Convergence of the Periodization of a Function

real-analysis

asked 5 mins ago DJG 133

0

votes

0

answers

3

views

Jacobian columns make basis for tangent spaces. Is there a relation between the signs of the basis transition matrix and of the transition jacobian?

determinant smooth-manifolds jacobian orientation transition-matrix

asked 5 mins ago orangefruits 1

2

votes

1

answer

16

views

Simplifying $\left( 2^{\aleph_\alpha}\right)^{\aleph_0}$

reference-request set-theory cardinals

answered 5 mins ago Mark Saving 6,896

1

vote

0

answers

17

views

How do I compute $\;\sum_{i=1}^{n} \sum_{j=1}^{i} \sum_{k=j}^{i+j} 1\;$?

algebra-precalculus summation

modified 6 mins ago Blue 65.7k

0

votes

0

answers

8

views

What is the mistake (Proof that $3 = 243$)?

modular-arithmetic

asked 6 mins ago learning123 486

0

votes

1

answer

13

views

Ring with multiplicative one equals to additive zero implies that the ring can only have one element

ring-theory

answered 9 mins ago QuantumSpace 16k

0

votes

0

answers

6

views

Finding rejection region

probability hypothesis-testing

asked 9 mins ago joseph 1

0

votes

1

answer

10

views

Poisson related homework question

probability probability-theory probability-distributions conditional-probability

answered 9 mins ago Jellyfish 9,069

0

votes

0

answers

5

views

decomposition of measure and Lp-spaces

measure-theory lebesgue-measure

asked 11 mins ago Liam 103

0

votes

0

answers

7

views

Derivative of the matrix exponential and power laws for matrices

linear-algebra matrix-calculus matrix-exponential

asked 13 mins ago FShrike 1,457

1

vote

0

answers

25

views

Show that $\dim(\rm ran(T))=\dim( \rm ran(T^∗))$

linear-algebra functional-analysis proof-explanation

modified 14 mins ago 20D 13

1

vote

0

answers

37

views

When does a group have a geometric realization?

group-theory geometry permutations euclidean-geometry symmetric-groups

modified 16 mins ago WhiteLake 340

2

votes

1

answer

26

views

Embedded surface in $\mathbb R^3$

algebraic-topology surfaces geometric-topology

answered 19 mins ago Connor Malin 8,817

1

vote

0

answers

7

views

Do these two max-min partition problems always have a common solution?

combinatorics set-partition

asked 19 mins ago Erel Segal-Halevi 9,467

0

votes

0

answers

4

views

Riemannian metric of a Kahler manifold

differential-geometry complex-geometry symplectic-geometry kahler-manifolds almost-complex

asked 19 mins ago blancket 1,646

0

votes

0

answers

8

views

Find the number of ways of inviting $9$ friends

combinatorics permutations combinations

asked 22 mins ago Ggsvdgdhddh 63

0

votes

0

answers

5

views

Taylor Series in Derivation of Euler Lagrange Equation

calculus-of-variations

asked 23 mins ago briduss 1

3

votes

0

answers

20

views

Invariance of divergence under arbitrary coordinate transformations

real-analysis multivariable-calculus differential-geometry divergence-operator

modified 27 mins ago levap 58.2k

0

votes

0

answers

28

views

Proof explanation: Why is $(f \circ \gamma)'(t) = f'(\gamma(t))(\gamma '(t))$?

multivariable-calculus proof-explanation

asked 29 mins ago Eduardo Magalhães 2,662

0

votes

2

answers

902

views

Desmos: How to define a constant implicitly?

graphing-functions calculator implicit-function

modified 31 mins ago Community♦ 1

2

votes

1

answer

18

views

How to expand the product of Laguerre polynomials into a sum of series？

summation power-series laguerre-polynomials

modified 32 mins ago Markus Scheuer 88.3k

1

vote

1

answer

13

views

For every $v\in V$, the MST of $G$, contains an edge, touching $v$, that has the minimal weight from all the edges touching $v$

graph-theory solution-verification

answered 34 mins ago mxian 1,424

0

votes

0

answers

5

views

Variation from on which variable is treated as a dependent variable

regression

asked 34 mins ago joseph 1

3

votes

1

answer

44

views

Confused about the derivation of the identity: $\ln(\zeta(s))=s\int_{0} ^ {\infty} J(x)x^{-s-1}dx$ and it's relationship to Stieltjes integrals

analytic-number-theory riemann-zeta stieltjes-integral

modified 35 mins ago Steven Clark 3,351

0

votes

0

answers

7

views

Reduction from VC to EVEN_VC

turing-machines

modified 35 mins ago Daniel 516

3

votes

1

answer

73

views

+100

Characteristics of equations of the form $u_{xy}=f(u_x,u_y,u)$

calculus ordinary-differential-equations partial-differential-equations

answered 38 mins ago Han de Bruijn 15.5k

0

votes

2

answers

47

views

Projective transformation four non-collinear points

projective-geometry

modified 1 min ago Somos 27.2k

0

votes

0

answers

21

views

what does it mean for polynomials to be the sum of constants multiples of powers of x?

calculus algebra-precalculus polynomials definition

asked 43 mins ago Rida EN-Nasry 29

-1

votes

0

answers

13

views

Convex inequality with 3 variables

inequality convexity-inequality

modified 24 secs ago MCuadros 13

-1

votes

0

answers

19

views

How to find basis [w]?

linear-algebra change-of-basis

asked 55 mins ago Jonte YH 119

3

votes

3

answers

504

views

Combinatorics Identity about Catalan numbers: $\sum_{k=0}^n \frac{1}{k+1}\binom{2k}k \binom{2n-2k}{n-k}=\binom{2n+1}n$

combinatorics summation binomial-coefficients catalan-numbers combinatorial-proofs

modified 59 mins ago Marko Riedel 53.1k

0

votes

0

answers

6

views

Assumptions on the random error in a linear regression model

expected-value regression variance

asked 1 hour ago joseph 1

0

votes

0

answers

6

views

Pole-polar duality map preserves convex polygons?

convex-geometry

asked 1 hour ago Steppewolf 64

0

votes

1

answer

16

views

Determining the equation of a line given angle with x-axis and other area related conditions

integration functions area

answered 1 hour ago Math Lover 29.6k

2

votes

0

answers

27

views

Approximation of Lebesgue measurable set

real-analysis measure-theory

modified 1 hour ago Yoona 85

0

votes

0

answers

27

views

Showing that the range is dense

real-analysis operator-theory

modified 1 hour ago Hrafn Magnus 61

1

vote

1

answer

36

views

Some tripartite graphs and DS graphs.

graph-theory spectral-theory

modified 1 hour ago Misha Lavrov 93.3k

0

votes

0

answers

13

views

How to choose a p.d. matrix $\Sigma$ s.t. $x^T\Sigma Mx$>0 for all $x$?

linear-algebra matrices eigenvalues-eigenvectors positive-definite symmetric-matrices

asked 1 hour ago a_student 808

0

votes

0

answers

14

views

Does solving the primal problem directly solve the dual?

optimization convex-optimization nonlinear-optimization lagrange-multiplier duality-theorems

asked 1 hour ago JMC 209

5

votes

2

answers

396

views

If $f \circ f =f$, then what is $f$?

real-analysis multivariable-calculus smooth-manifolds functional-equations

answered 1 hour ago levap 58.2k

0

votes

0

answers

10

views

The graph of a bounded function is $J$- measurable

integration lebesgue-integral lebesgue-measure

modified 1 hour ago Arturo Magidin 338k

1

vote

1

answer

31

views

The difference of two Brownian Processes

probability-distributions stochastic-processes brownian-motion

answered 1 hour ago Snoop 2,880

0

votes

1

answer

28

views

How to find the definite integral when the antiderivative is dependent on intervals?

integration trigonometry definite-integrals

modified 1 hour ago José Carlos Santos 349k

1

vote

0

answers

18

views

Cut off function on complete Riemannian manifolds

differential-geometry riemannian-geometry

modified 1 hour ago Quang Huy Trần 81

0

votes

0

answers

16

views

Groups of endomorphisms and automorphisms, bases paradox?

linear-algebra general-linear-group

modified 1 hour ago user12692470 11

1

vote

0

answers

31

views

Prove $10^{P(n)/2}+1$ is divisible by $n$

elementary-number-theory modular-arithmetic divisibility decimal-expansion

asked 1 hour ago ordptt 365

0

votes

0

answers

17

views

A question related to a deducing a result related to degree of a polynomial

number-theory

modified 1 hour ago Bernard 166k

1

vote

1

answer

27

views

Expectation of a local martingale and uniform integrability

probability-theory stochastic-processes stochastic-calculus martingales stochastic-differential-equations

answered 1 hour ago Rhys Steele 16.5k

0

votes

0

answers

15

views

Does the braid group $B_n$ have a (non-trivial) subnormal automorphism?

automorphism-group braid-groups

asked 1 hour ago LigourasP 1

1

vote

0

answers

26

views

How many “2-times” exist between two given digital times

combinatorics coding-theory

asked 1 hour ago stephanie 11

0

votes

1

answer

44

views

Optimization of trace of a matrix

optimization matrix-calculus pseudoinverse trace-map

modified 1 hour ago greg 23.1k

2

votes

0

answers

55

views

How to check if splitting fields of different polynomials share a subfield?

abstract-algebra field-theory galois-theory

modified 1 hour ago HallaSurvivor 17.7k

1

vote

0

answers

8

views

Support of convolution of bump function with surface measure

linear-algebra analysis

asked 2 hours ago JasonJones 784

0

votes

0

answers

20

views

Chern character of a coherent sheaf over a projective manifold

algebraic-geometry reference-request complex-geometry vector-bundles coherent-sheaves

asked 2 hours ago BinAcker 457

2

votes

2

answers

39

views

Find segment ratio when three points form three lines dividing area of equilateral triangle evenly

geometry area

modified 2 hours ago Andrei 27.6k

0

votes

0

answers

11

views

Showing that a sequence does not have an analytic extension of exponential type

complex-analysis analysis interpolation-theory

modified 2 hours ago zbrads2 779

1

vote

0

answers

14

views

Proving language from Hamming Distance is regular

automata regular-language

modified 2 hours ago retiredmonk 43

0

votes

0

answers

10

views

Question Regarding Sample Standard Deviation versus Population Standard Deviation

standard-deviation central-limit-theorem standard-error

asked 2 hours ago robert5722 1

0

votes

0

answers

21

views

When will the ac-method of factorization work?

factoring

modified 2 hours ago snowape 123

0

votes

0

answers

9

views

Does there exist a geodesic $\gamma_p$ through $p$ such that the reflection along it, say $r_{\gamma_p}$ gives $r_{\gamma_p}(q_2)=q_1$?

riemannian-geometry hyperbolic-geometry geodesic reflection

asked 2 hours ago user8897 98

3

votes

1

answer

34

views

How can we show $\int_0^xu^{-\alpha}(t,r)u_r(t,r)\:{\rm d}r=\frac{u^{1-\alpha}(t,x)-u^{1-\alpha}(t,0)}{1-\alpha}$?

real-analysis integration partial-differential-equations parabolic-pde

modified 2 hours ago 0xbadf00d 11.9k

1

vote

1

answer

30

views

Is my method correct to find Minimal Polynomial for a $5\times 5$ triangular matrix?

matrices minimal-polynomials block-matrices

modified 2 hours ago Jochen 437

7

votes

1

answer

244

views

Paper cylinder inside out

geometry surfaces

answered 2 hours ago Narasimham 34.3k

0

votes

0

answers

27

views

Show that there exist a linear operator

linear-algebra

modified 2 hours ago Algebrology 901

0

votes

1

answer

13

views

For what value $\alpha$ is the variance of $\operatorname{Par}(\alpha)$ distribution finite?

probability probability-distributions

answered 2 hours ago grand_chat 29.9k

0

votes

0

answers

15

views

Cayley map on the upper half plane and the unit disk

complex-analysis complex-numbers

modified 2 hours ago Bernard 166k

0

votes

1

answer

17

views

What Statistical Test to choose for data of sales numbers.

probability probability-theory statistics hypothesis-testing

answered 2 hours ago Jellyfish 9,069

0

votes

0

answers

23

views

Is this subspace L-embedded?

functional-analysis banach-algebras

modified 2 hours ago doc 31

0

votes

0

answers

18

views

Calculating the limit of the vector function

calculus ordinary-differential-equations limits vector-fields

asked 2 hours ago Curious Cosmopolitan 83

0

votes

0

answers

12

views

discussion of the truncation error derived using a Taylor expansion

partial-differential-equations finite-differences

asked 2 hours ago Ahmetabi 1

4

votes

1

answer

127

views

+100

Help showing $y \cdot f(x+1) \leq \frac{C_0(p) \cdot y \cdot f(y)}{2} + \frac{x \cdot f(x)}{2}$

functions polynomials proof-explanation game-theory

modified 2 hours ago mathlove 117k

19

votes

4

answers

4k

views

Inequality. $\frac{1}{16}(a+b+c+d)^3 \geq abc+bcd+cda+dab$

inequality

modified 2 hours ago Blitzer 728

0

votes

0

answers

18

views

Why do $P$-groups have a local basis of open subgroups?

general-topology topological-groups

asked 2 hours ago TopologicalDynamitard 115

0

votes

0

answers

15

views

Good differential geometry/differential topology text to read after Analysis on Manifolds?

reference-request soft-question

asked 2 hours ago Luna145 1,591

0

votes

0

answers

19

views

Associated Legendre Equation truncation

ordinary-differential-equations legendre-polynomials

modified 3 hours ago Phineas Nicolson 161

1

vote

0

answers

20

views

Group of Jacobians of on $C^\infty$ real manifold.

group-theory manifolds jacobian

asked 3 hours ago Tanmay Singal 11

0

votes

0

answers

16

views

A doubt from product constancy.

arithmetic percentages

asked 3 hours ago Nayanthara Thomas 1

1

vote

0

answers

26

views

Vector valued representer theorem for objective over output space

functional-analysis optimization machine-learning reproducing-kernel-hilbert-spaces

modified 3 hours ago math 3,615

1

vote

0

answers

22

views

+50

Relationship between weights in the minimization of a weighted average and the slopes of the function at the optimum

optimization

modified 3 hours ago Patricio 1,143

1

vote

1

answer

31

views

Why are uncertainties calculated as an average?

average error-propagation

answered 3 hours ago learning123 486

1

vote

1

answer

28

views

$|E:F|=1$ if $char(k)=0$ and $p^m$ for some $m \in \mathbb N \cup \{0\}$ if $char(k)=p$.

field-theory galois-theory extension-field splitting-field

modified 3 hours ago user371231 2,114

1

vote

0

answers

11

views

Proving the tangent hyperconic of an algebraic hypersurface $V(f)$ is indeed a hyperconic

algebraic-geometry

modified 3 hours ago PaleBlueDot 692

5

votes

0

answers

41

views

Which non-compact quaternion-Kähler spaces are Kähler?

reference-request complex-geometry kahler-manifolds symmetric-spaces

modified 3 hours ago AMA 51

1

vote

0

answers

15

views

What happens if I do a fractional number of Bernoulli trials?

probability probability-distributions soft-question poisson-distribution

asked 3 hours ago Kevin 2,066

2

votes

0

answers

23

views

On the uniqueness statement in the Eckart–Young–Mirsky theorem

linear-algebra proof-explanation norm matrix-rank svd

modified 3 hours ago Alphie 2,057

1

vote

0

answers

17

views

What is the math term for a trilateral orthogonal pyramid with a right-angle triangle in the base?

geometry euclidean-geometry terminology plane-geometry

modified 3 hours ago Blue 65.7k

5

votes

0

answers

86

views

How to rewrite $\int\limits_A^B \frac{x^n \exp(-\alpha x)}{\small(x + \beta\small)^m} \, dx$?

integration improper-integrals special-functions

modified 3 hours ago Thai-Hoc Vu 53

1

vote

0

answers

16

views

Conditions for Kernel coercivity on a bilinear form

functional-analysis hilbert-spaces bilinear-form coercive

asked 4 hours ago DMDemon 11

1

vote

0

answers

13

views

Computing shortest decomposition of a permutation as product of 2-cycles.

abstract-algebra discrete-mathematics permutations

asked 4 hours ago hrkrshnn 5,901

1

vote

1

answer

45

views

Simplifying $\sum_{k=1}^n F_kF_{k+3}$

algebra-precalculus summation fibonacci-numbers

modified 4 hours ago Blue 65.7k

2

votes

0

answers

22

views

A complex orthonormal basis induces a real orthonormal basis

vector-spaces inner-products orthogonality orthonormal almost-complex

asked 4 hours ago blancket 1,646

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