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Bounding the size of the inverse of $I+AB$ when $A$ and $B$ are both PSD

matrices inverse positive-semidefinite matrix-norms spectral-norm

answered 1 min ago JimmyK4542 42.2k

1

vote

1

answer

18

views

Optimization with bilinear constraint

optimization convex-optimization nonlinear-optimization bilinear-form

modified 1 min ago Rodrigo de Azevedo 13.5k

8

votes

2

answers

65

views

The integral $\int_{0}^{\pi/2} \sin 2\theta ~ \mbox{erf}(\sin \theta)~ \mbox{erf}(\cos \theta)~d\theta=e^{-1}$

definite-integrals

modified 1 min ago user10354138 17.1k

0

votes

0

answers

3

views

How can I numerically implement $\delta(f(x,y))$

numerical-methods dirac-delta

asked 2 mins ago Tanmay Bhore 1

0

votes

0

answers

11

views

Does no duality gap imply global optimum for QP?

optimization quadratic-programming non-convex-optimization

modified 4 mins ago Rodrigo de Azevedo 13.5k

0

votes

0

answers

2

views

Determined the number of different letter permutation, of any length, that can be made using the letters LOTTO.

probability

asked 5 mins ago Mathenatic 58

0

votes

0

answers

2

views

Confusion with maps between graded vector space and DGA

homology-cohomology

asked 6 mins ago sasho98 1

0

votes

1

answer

42

views

If $A \in M_2(\mathbb{C})$ and $A^2 = 0$ then what are the possible forms of A?

linear-algebra matrices jordan-normal-form nilpotence

modified 6 mins ago Rodrigo de Azevedo 13.5k

0

votes

0

answers

6

views

How many circles can fit on the perimeter of N-gon

geometry circles polygons

asked 6 mins ago Marko Taht 149

0

votes

0

answers

17

views

Distribution function of $\sin(\pi\theta)$ when $\theta\sim U(-1,1)$

probability probability-distributions uniform-distribution

modified 8 mins ago StubbornAtom 7,475

0

votes

0

answers

16

views

Recurrent chain rule

derivatives neural-networks

modified 10 mins ago Curious 16

4

votes

0

answers

29

views

Examples of surfaces with constant curvatures

differential-geometry riemannian-geometry examples-counterexamples hyperbolic-geometry spherical-geometry

modified 11 mins ago Rodrigo de Azevedo 13.5k

1

vote

1

answer

65

views

problem with Exterior Derivative

differential-geometry differential-forms exterior-algebra

modified 12 mins ago exxxit8 77

5

votes

1

answer

685

views

Question Relating with Open Mapping Theorem for Analytic Functions

complex-analysis analyticity

modified 12 mins ago Community♦ 1

1

vote

0

answers

17

views

Trace inequality related to the product of three matrices

matrices proof-verification matrix-norms

modified 13 mins ago user1551 76.4k

0

votes

0

answers

7

views

What is meant by Atomic Spectrum of operator?

functional-analysis operator-theory

asked 13 mins ago Ali 11

0

votes

1

answer

15

views

Chance of one occurrence having a larger score than another

probability standard-deviation

modified 22 mins ago Ajay Mishra 614

0

votes

2

answers

10

views

Find the area of triangle SVW

trigonometry area

answered 23 mins ago Epiksalad 172

2

votes

3

answers

386

views

When is an integrally closed local domain a valuation ring?

ring-theory commutative-algebra local-rings

answered 25 mins ago Badam Baplan 4,832

0

votes

0

answers

15

views

Equivalent to Tao's Analysis 1 Book for Statistics

statistics reference-request book-recommendation

modified 25 mins ago Thomas Shelby 5,662

0

votes

1

answer

16

views

Integration using substitution - applying integral of symmetric functions properties or second substitution?

calculus integration definite-integrals

modified 29 mins ago Chris Custer 16.7k

0

votes

1

answer

23

views

Calabi–Yau condition

complex-geometry vector-bundles

modified 30 mins ago Eric Wofsey 200k

0

votes

1

answer

8

views

How do i count number of outcomes of a dice roll using a formula?

probability combinatorics dice

answered 30 mins ago Epiksalad 172

2

votes

2

answers

51

views

Entire function such that $f(z) = a f(z+1)= b f(z+i)$

complex-analysis

modified 31 mins ago metamorphy 5,797

0

votes

0

answers

9

views

Condition for a normalized 2-cocycle from the existence of the inverse element in a group extension

group-theory group-cohomology

modified 32 mins ago mma 646

0

votes

0

answers

10

views

Quadratic variation of logarithm of Bessel process

stochastic-processes sde quadratic-variation

asked 32 mins ago IchKenneDeinenNamen 36

0

votes

0

answers

12

views

How can one prove that the function is 2-cocycle?

complex-analysis lie-algebras homology-cohomology

modified 33 mins ago John Watson 84

0

votes

1

answer

23

views

Can you take out a common factor when taking a derivative of a vector function?

calculus derivatives vectors

modified 36 mins ago user326210 10.4k

0

votes

0

answers

7

views

Renewal process inter arrival mean time math

probability statistics renewal-processes

asked 38 mins ago Tasbiul Islam Nibir 1

-1

votes

0

answers

6

views

Volume of Prismatoid

geometry solid-geometry

asked 45 mins ago Jan Navasca 36

-1

votes

0

answers

20

views

If $y = \sin^{-1} x$, show that, $(1 - x^2) y_5 - 7xy_4 - 9y_3 = 0$

calculus

modified 48 mins ago Theo Bendit 23.8k

6

votes

3

answers

529

views

How to decide about the convergence of $\sum(n\log n\log\log n)^{-1}$?

calculus real-analysis sequences-and-series analysis convergence

modified 56 mins ago Saaqib Mahmood 8,434

1

vote

0

answers

7

views

Asymptotically logarithmic power series for $z\to 1$ with positive coefficients

asymptotics power-series

asked 58 mins ago Jfischer 33

2

votes

1

answer

29

views

Why is it a consequence of a notational choice that left actions are covariant functors?

category-theory notation functors

modified 59 mins ago Arthur 130k

1

vote

1

answer

14

views

Prove $\{A\cap E:A\in\mathcal A\}$ is a $\sigma-algebra$ of $E$

measure-theory proof-verification elementary-set-theory

answered 1 hour ago Kavi Rama Murthy 92k

-1

votes

0

answers

22

views

Taylor Series and Euler's Number

limits convergence taylor-expansion limits-without-lhopital divergence

modified 1 hour ago Ajay Mishra 614

0

votes

0

answers

8

views

Median of subset of unknown distribution

statistics statistical-inference descriptive-statistics

asked 1 hour ago Fabrizio 1

0

votes

0

answers

11

views

Welch-Gong permutation proof in $GF(2^8)$

permutations proof-explanation finite-fields

asked 1 hour ago hardyrama 150

0

votes

1

answer

17

views

Finding extrema, non-critical points, and saddle points given a contour plot

multivariable-calculus graphing-functions

modified 1 hour ago Ajay Mishra 614

1

vote

0

answers

14

views

How to prove that the gradient of a function is Lipschitz continuous?

lipschitz-functions gradient-descent

asked 1 hour ago Danny_Kim 1,401

0

votes

0

answers

14

views

Representing linear operators

linear-algebra

asked 1 hour ago Magician2019 6

0

votes

1

answer

15

views

relation between $\sup_{0\leq s\leq t}|W_s|$ and $\sup_{0\leq s\leq t}W_s$ where $W$ is a Brownian motion.

probability brownian-motion

answered 1 hour ago saz 85.4k

0

votes

1

answer

25

views

Proof that the set $\left\{ {\cos \left( {\frac{{n\pi x}}{L}} \right)} \right\}_{n\,\, = \,\,0}^\infty$ is orthogonal

calculus trigonometry

answered 1 hour ago Kavi Rama Murthy 92k

2

votes

5

answers

108

views

A continuous function $f:[a,b] \to \mathbb{R}$ that is monotonic on $(a,b)$ is also monotonic on $[a,b]$

real-analysis calculus general-topology

modified 1 hour ago Kaj Hansen 28.1k

0

votes

1

answer

12

views

Expectation of multiplied matrices

linear-algebra statistics

answered 1 hour ago pre-kidney 14.7k

1

vote

0

answers

6

views

Continuity of a differential of a Banach-valued holomorphic map

complex-analysis reference-request complex-geometry several-complex-variables

asked 1 hour ago erz 458

0

votes

1

answer

18

views

Why is Expectation[ $B_t^4] = 3t^2$?

stochastic-processes stochastic-calculus

modified 1 hour ago pre-kidney 14.7k

0

votes

0

answers

9

views

Function to translate from two 90 deg shifted triangle waves to a rotation angle?

functions transformation

asked 1 hour ago norlesh 101

2

votes

1

answer

27

views

How to show that this multivariable limit exists or not?

limits multivariable-calculus

modified 1 hour ago Thomas Shelby 5,662

0

votes

0

answers

27

views

Find every $a \in \mathbb{R}$ such that $f = X^{2n+1} - (2n+1)X + a$ has a repeated root

polynomials complex-numbers roots-of-unity

modified 1 hour ago Davood Khajehpour 3,764

0

votes

1

answer

29

views

Soft Question about Lipschitz functions: $\inf_{y \in \mathbb{R}}\{u(y) + td(x,y) \}$

measure-theory soft-question proof-explanation

modified 1 hour ago User8128 11.5k

0

votes

0

answers

11

views

Can the Binary Icosahedral Group be represented in terms of (small) permutation groups

finite-groups permutations representation-theory

asked 1 hour ago tippy2tina 46

6

votes

3

answers

182

views

Evaluate the definite integral $\int_0^{2\pi}\arctan\left((a\cos x + b\sin x)^2\right)dx$

calculus integration definite-integrals

modified 1 hour ago metamorphy 5,797

1

vote

1

answer

25

views

Prove that the limit of zeroes of a non zero complex valued function is an essential singularity of the function

complex-analysis singularity

answered 1 hour ago Kavi Rama Murthy 92k

0

votes

0

answers

21

views

Ideals generated by regular sequence in regular local ring

algebraic-geometry commutative-algebra

modified 1 hour ago user26857 39.8k

11

votes

0

answers

55

views

The “natural” Sophomore's Dream integral: $\int_{0}^{\infty} x^{-x}\ dx$

calculus integration definite-integrals

asked 1 hour ago The_Sympathizer 9,318

0

votes

1

answer

16

views

Find n in arithmetic sequence

algebra-precalculus

answered 1 hour ago sirous 1,905

6

votes

1

answer

217

views

+50

Catenary Cable Problem: Timoshenko (2 solvers since last year only)

calculus mathematical-physics maxima-minima classical-mechanics

modified 1 hour ago learningstudent 366

1

vote

2

answers

62

views

The minimum timescales to reach a population of 1 Trillion people

soft-question exponential-function arithmetic

answered 2 hours ago David K 57.3k

0

votes

1

answer

23

views

Framing as unusual, 3rd degree polynomial

algebra-precalculus

answered 2 hours ago Macavity 36.2k

0

votes

1

answer

24

views

Verifying maxima/minima in Lagrange multipliers method

calculus multivariable-calculus lagrange-multiplier maxima-minima

answered 2 hours ago John Wayland Bales 15.8k

53

votes

10

answers

12k

views

Stirling's formula: proof?

limits asymptotics gamma-function factorial

modified 2 hours ago robjohn♦ 274k

-1

votes

0

answers

30

views

+50

Taking the logarithm of an exponent having a complicated power term

logarithms exponential-function

modified 2 hours ago nashynash 64

3

votes

1

answer

21

views

Rothberger game and Meager set.

general-topology infinite-games

modified 2 hours ago Martin Sleziak 46.2k

0

votes

1

answer

44

views

What is the most concise and morally correct way to express this operation?

matrices

answered 2 hours ago pre-kidney 14.7k

1

vote

0

answers

37

views

Use of Axiom of Choice in Baire Category Theorem

metric-spaces axiom-of-choice baire-category

modified 2 hours ago Martin Sleziak 46.2k

1

vote

1

answer

16

views

Expectation of trace and trace of expectation

linear-algebra statistics

answered 2 hours ago pre-kidney 14.7k

2

votes

1

answer

42

views

Why does a vector bundle have the same first Chern class as its determinant bundle?

vector-bundles characteristic-classes

modified 2 hours ago Eric Wofsey 200k

-2

votes

0

answers

7

views

How to solve general inhomogeneous Bessel equation in cylindrical coordinates

pde

asked 2 hours ago fatima 1

0

votes

0

answers

25

views

How to solve a linear difference equation?

ordinary-differential-equations numerical-methods recurrence-relations

modified 2 hours ago nmasanta 2,147

0

votes

1

answer

29

views

Continuous mapping theorem, multivariate case, joint distribution.

probability-theory convergence stochastic-analysis

modified 2 hours ago kimchi lover 14.3k

2

votes

1

answer

33

views

Understanding stability of numerical ODE methods from just linear problem

ordinary-differential-equations numerical-methods

modified 2 hours ago nmasanta 2,147

1

vote

1

answer

25

views

Adding trig functions with different frequencies

trigonometry

modified 2 hours ago nmasanta 2,147

0

votes

0

answers

8

views

What is Dirichlet norm?

matrices geometry graph-theory

asked 2 hours ago ezla.hb 45

0

votes

0

answers

23

views

Conditional distribution of $\angle X$ for $X \in \mathbb{R}^2 \sim \mathcal{N}(\mu, \Sigma)$ given that $|X| = a$

normal-distribution conditional-probability

modified 2 hours ago Brian 262

1

vote

1

answer

23

views

Are vector bundles with isomorphic determinant bundles isomorphic?

vector-bundles exterior-algebra

modified 2 hours ago Eric Wofsey 200k

0

votes

0

answers

25

views

Finding if a function is in some space and derivation of a Dirac delta function

distribution-theory

modified 2 hours ago nmasanta 2,147

0

votes

0

answers

8

views

Transitivity of regular extensions

field-theory

asked 2 hours ago Jaakko Seppälä 1,313

0

votes

0

answers

11

views

Is the ring product of Euclidean rings (not necessarily integral domains) also Euclidean?

abstract-algebra ring-theory

asked 2 hours ago len 8

0

votes

0

answers

9

views

Local Complete Intersections

algebraic-geometry schemes

modified 2 hours ago KarlPeter 765

1

vote

0

answers

19

views

Restrictions on matrix such that it multiplies an integer matrix to form another integer matrix

linear-algebra matrices elementary-number-theory

asked 2 hours ago PPenguin 367

4

votes

0

answers

21

views

What is the matrix of the monster Lie algebra?

modular-forms kac-moody-algebras

asked 3 hours ago Aidan Backus 159

1

vote

4

answers

505

views

Problem 17 in chapter 3 of Spivak book

calculus real-analysis algebra-precalculus

answered 3 hours ago Rivfader 1

0

votes

0

answers

6

views

chain connected and pointwise boundedness of an equicontinuous family of functions

analysis metric-spaces

asked 3 hours ago a.p 13

0

votes

0

answers

7

views

Adjusting normally distributed values for another variable

statistics normal-distribution

asked 3 hours ago memokerobi 10

1

vote

0

answers

23

views

How to find the form of series solution $2x^2y'' + 5(e^x-1)y'+cosh(x)y=0$

ordinary-differential-equations power-series frobenius-method

modified 3 hours ago crown 11

0

votes

1

answer

8

views

Frechet Filter and Principal Filter

elementary-set-theory

answered 3 hours ago William Elliot 10k

2

votes

1

answer

27

views

Prove $f(a)^2\sin(2a)=f(b)^2\sin(2b)$ for every closed curve given by $(f(t)\cos(t),f(t)\sin(t))$

calculus multivariable-calculus differential-geometry

answered 3 hours ago Piquito 18.5k

2

votes

2

answers

39

views

Rudin 5.11. Second order derivative

real-analysis

modified 4 hours ago peek-a-boo 2,260

14

votes

0

answers

430

views

+200

Interpreting the scalar curvature in a semi-Riemannian manifold

differential-geometry riemannian-geometry general-relativity semi-riemannian-geometry

modified 4 hours ago tcamps 3,161

1

vote

0

answers

18

views

Spectrum of conjugate linear maps

real-analysis functional-analysis proof-verification

asked 4 hours ago RandomWalker 223

1

vote

1

answer

15

views

Negation Normal Form and the length of formulas

logic propositional-calculus

modified 4 hours ago ShyPerson 1,024

1

vote

0

answers

37

views

Why does Huffman encoding have entropy?

information-theory entropy

modified 5 hours ago liang 124

5

votes

0

answers

38

views

TDA and knot theory

algebraic-topology knot-theory data-analysis topological-data-analysis

modified 5 hours ago Seewoo Lee 8,146

0

votes

1

answer

17

views

every irreducible component of $Y \cap H$ has dimension $r-1$

abstract-algebra algebraic-geometry polynomials commutative-algebra dimension-theory

answered 7 hours ago Mohan 12.1k

0

votes

0

answers

5

views

Relative angle in transformed coordinates with respect to particle position and velocity

linear-transformations vector-analysis rotations

modified 7 hours ago Junaid Mehmood 1

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