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12

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Confused by the many versions of Hahn-Banach Separation Theorem

real-analysis general-topology functional-analysis

modified 6 mins ago user141240 449

0

votes

1

answer

4

views

Conditional expectation of X-Y given Y=5

conditional-expectation

answered 6 mins ago someeed 128

1

vote

1

answer

15

views

When a function is integrated from a to b, does x equal a/b or they just tend to those limits?

integration limits definite-integrals

answered 6 mins ago Firdous Ahmad Mala 1,029

0

votes

0

answers

9

views

Derivative definition for root functions

calculus

asked 9 mins ago Sharmin Aeheli 51

0

votes

0

answers

6

views

Proving that quotient space is Hausdorff

general-topology quotient-spaces

asked 11 mins ago Alejandra Benítez 310

2

votes

2

answers

43

views

A differential equation and coordinate geometry problem

calculus ordinary-differential-equations analytic-geometry

modified 12 mins ago Jean Marie 58.5k

0

votes

0

answers

22

views

Dividing into two groups so no person has more than one enemy in their group

solution-verification recreational-mathematics problem-solving

modified 15 mins ago Greg Martin 58.2k

0

votes

0

answers

3

views

Limit point of a segment in (ambient space) $\mathbb R^2$

real-analysis metric-spaces normed-spaces

asked 15 mins ago Raj Panse 375

0

votes

0

answers

5

views

Construct a quadrangulation with connectivity 2 and minimum degree 3

graph-theory planar-graphs

modified 16 mins ago licheng 631

1

vote

0

answers

7

views

Growth rate / bounds for a recursive function of two-variables.

asymptotics recursion upper-lower-bounds

modified 19 mins ago Graviton 3,351

1

vote

0

answers

40

views

+50

How to evaluate this integral using contiour integration( Help needed in choosing contour)

complex-analysis residue-calculus

modified 20 mins ago No -One 1,230

1

vote

1

answer

1k

views

Given the following transformation rule and the coordinates of the image, find the coordinates of the Pre-Image

geometry triangles

modified 21 mins ago Community♦ 1

-1

votes

0

answers

16

views

Let $n \geq 2$ be an integer and let $M_n(\mathbb{R})$ denote the space of $n \times n$ real matrices.

linear-algebra matrices matrix-rank

modified 23 mins ago Brian Moehring 12.2k

0

votes

0

answers

4

views

Help with finding distribution of Gaussian mixture

probability probability-distributions stochastic-processes

asked 24 mins ago Bgdk284 23

0

votes

0

answers

7

views

solving Moore-Penrose inverse

linear-algebra

asked 25 mins ago someeed 128

12

votes

1

answer

328

views

+50

What is $\mathcal{R}$?

sequences-and-series closed-form gamma-function products spheres

modified 37 mins ago Rounak Sarkar 1,331

2

votes

0

answers

633

views

Proof of Mantel's Theorem

graph-theory solution-verification

modified 39 mins ago orangeskid 41.3k

0

votes

0

answers

6

views

Is possible set up a homeomorphism over a singular isolate point?

general-topology analysis topological-vector-spaces singular-values

asked 41 mins ago JELV 61

0

votes

0

answers

52

views

Probability of ultimate extinction of a branching Markov chain

probability stochastic-processes markov-chains

modified 43 mins ago Ethan Mark 1,834

0

votes

3

answers

23

views

How many 4 digit numbers in the octal number system exist such that they are formed using exactly three distinct digits?

combinatorics solution-verification combinations

answered 47 mins ago fleablood 115k

1

vote

0

answers

28

views

Is it okay if a function has two different points that have the exact same coordinates?

functions elementary-set-theory

modified 47 mins ago J.-E. Pin 33.1k

1

vote

0

answers

21

views

How to construct a symmetric $n \times n$ matrix whose rank is $s$ and every $s\times s$ submatrix of it is full rank?

linear-algebra matrix-rank symmetric-matrices

modified 47 mins ago Sepide 935

1

vote

0

answers

25

views

How to Prove $\sum_{k=1}^{n} \Theta(f(k)) = \Theta(\sum_{k=1}^{n} f(k))$

algorithms

modified 48 mins ago Mrigank Vallabh 31

4

votes

2

answers

123

views

Prove that: $\sum\limits_{cyc}\frac{1}{\sqrt{2a^2+5ab+2b^2}} \geq\sqrt{\frac{3}{ab+ac+bc}}$

inequality contest-math alternative-proof holder-inequality uvw

modified 55 mins ago Michael Rozenberg 182k

0

votes

0

answers

14

views

Probability of a given 5 letter word occurring at a given position in 1000000 randomly typed letters.

probability

asked 57 mins ago random math student 7

0

votes

0

answers

36

views

A function f : (a, b) → R is a convex function if for all x, y ∈ (a, b) and all s, t ∈ [0, 1] with s + t = 1 we have f(sx + ty) ≤ sf(x) + tf(y).

real-analysis

modified 57 mins ago Oliver Diaz 20.5k

0

votes

1

answer

18

views

Queries on the concept of a closed subspace

real-analysis metric-spaces hilbert-spaces banach-spaces normed-spaces

modified 59 mins ago Kavi Rama Murthy 276k

2

votes

0

answers

7

views

Complex Fourier Transform Bounds of Integration

fourier-analysis fourier-transform integral-transforms

asked 1 hour ago znc204 31

0

votes

1

answer

16

views

Probability of a Component Lasting More than 6 Months

probability probability-distributions

modified 1 hour ago angryavian 74.3k

2

votes

0

answers

20

views

Prove $(tr_B(\rho^{AB}))_{aa'}=\sum_{b}\rho^{AB}_{ab,a'b}=\rho^{A}_{aa'}$

linear-algebra tensor-products trace quantum-mechanics

modified 1 hour ago Sooraj S 6,399

1

vote

1

answer

9

views

How is the notation in this Hessian Matrix calculated?

derivatives hessian-matrix

answered 1 hour ago angryavian 74.3k

0

votes

0

answers

11

views

Help with equating probability expression (showing Markov process)

probability

asked 1 hour ago Bgdk284 23

0

votes

0

answers

9

views

Solving system of rational recurrence relations related to Fibonacci sequence

sequences-and-series discrete-mathematics recurrence-relations fibonacci-numbers nonlinear-system

asked 1 hour ago A.O. 1

1

vote

0

answers

18

views

The convex cone of a compact set not including the origin is always closed?

general-topology analysis convex-analysis compactness convex-geometry

modified 1 hour ago Ethanabc 527

1

vote

0

answers

13

views

Number of different value of given expression for $x,y,z \in \{1,2,3,4,5\}$

combinatorics algebra-precalculus

asked 1 hour ago Akira 723

0

votes

0

answers

41

views

Question regarding exponentiation Terence Tao Analysis 1

real-analysis exponentiation

modified 1 hour ago DeBARtha 486

0

votes

0

answers

20

views

Evaluation of an improper double integral numerically

integration fourier-transform numerical-calculus

modified 1 hour ago metamorphy 27.6k

1

vote

0

answers

9

views

Convexity of Root Quadratic Forms of Inverse P.D. Matrices.

linear-algebra matrices convex-analysis quadratic-forms positive-definite

asked 1 hour ago ChubbyRuby 81

-2

votes

0

answers

13

views

Three Set Venn Diagrams given probabilities

probability

modified 1 hour ago Firdous Ahmad Mala 1,029

0

votes

1

answer

22

views

Expected value of a function, is this true? why?

probability expected-value conditional-expectation

answered 1 hour ago 5201314 2,129

0

votes

1

answer

27

views

Explicit basis for orthogonal subspace in polynomial form

polynomials commutative-algebra

modified 1 hour ago user26857 45.8k

0

votes

2

answers

19

views

Negate the following sentence.

quantifiers

answered 1 hour ago ndhanson3 1,098

2

votes

0

answers

16

views

+50

Finding the gradient of the restricted function in terms of the gradient of the original function

derivatives partial-derivative jacobian

modified 1 hour ago Sepide 935

1

vote

0

answers

34

views

Interesting growing behaviour of hypergeometric function

real-analysis complex-analysis asymptotics hypergeometric-function

modified 1 hour ago principal-ideal-domain 4,755

0

votes

0

answers

14

views

Triple Intergal in spherical coordinates

calculus multivariable-calculus 3d spherical-coordinates

asked 1 hour ago Syed Tallay Haidar 1

0

votes

1

answer

12

views

Compound of Binomial and Poisson random variable

probability-distributions random-variables conditional-probability poisson-distribution binomial-distribution

modified 1 hour ago Graham Kemp 115k

2

votes

0

answers

16

views

Is $xyz=k^3$ a developable surface

differential-geometry

modified 1 hour ago math 385

0

votes

2

answers

625

views

Chinese Remainder Theorem whose modulus are not coprime

number-theory elementary-number-theory chinese-remainder-theorem

modified 1 hour ago steven gregory 25k

1

vote

0

answers

37

views

What is the mechanism happening in defining twisted module?

algebraic-geometry commutative-algebra

modified 1 hour ago Why 6,793

0

votes

0

answers

12

views

Divisibility into k tuples of primes.

number-theory prime-numbers divisibility arithmetic-progressions

asked 1 hour ago Luis Alexandher 449

0

votes

0

answers

29

views

+50

Function $\epsilon(s, \chi) $ related to Dirichlet L -function

number-theory analytic-number-theory dirichlet-series

modified 1 hour ago No -One 1,230

0

votes

0

answers

6

views

Methods for "measuring dependence" in a stochastic process

probability-theory stochastic-processes soft-question independence coupling

asked 2 hours ago The Substitute 4,107

-1

votes

0

answers

17

views

Regarding OEIS and integer sequences

oeis integer-sequences

asked 2 hours ago Firdous Ahmad Mala 1,029

0

votes

1

answer

11

views

Use Neighbourhood system to recover a topological space, the "new" neighbourhood system is just the "old" one

general-topology

answered 2 hours ago Reveillark 11.9k

0

votes

0

answers

9

views

Question regarding why the area under the Normal Distribution Curve gives us the Probability

probability-distributions normal-distribution

asked 2 hours ago Harry Case 85

0

votes

0

answers

9

views

Automorphism groups of curves

elliptic-curves algebraic-curves automorphism-group

asked 2 hours ago Kirill Losev 437

-1

votes

0

answers

34

views

Longest element of a monoid

group-theory monoid

modified 2 hours ago Tim Lee 61

1

vote

1

answer

24

views

Concrete mathematics: Computing the value of certain infinite sums example

discrete-mathematics

answered 2 hours ago grand_chat 30.4k

-1

votes

0

answers

17

views

The Grassmannian G(k,n) is the set of all k-planes through the origin in R". Such a k-plane is a linear subspace of dimension k of R" and has a basis

manifolds

asked 2 hours ago KOUKI 7

0

votes

0

answers

18

views

Existence of prime ideals for commutative rings

algebraic-geometry commutative-algebra

asked 2 hours ago Deepleeqe 365

-2

votes

0

answers

18

views

Function of Random Variable and then finding probability

probability-theory probability-distributions random-variables uniform-distribution gamma-distribution

modified 2 hours ago Firdous Ahmad Mala 1,029

4

votes

1

answer

30

views

Abelian Subgroup of Normal Subgroup of Solvable Group

abstract-algebra group-theory abelian-groups normal-subgroups solvable-groups

answered 2 hours ago Brauer Suzuki 889

2

votes

0

answers

49

views

Expression for ways of choosing k out of n objects placed in a circle such that r of them are consecutive.

combinatorics

modified 2 hours ago Dhruv Pratap Singh 21

0

votes

1

answer

23

views

Limit Points and Sups

analysis

answered 2 hours ago Adam T 161

2

votes

0

answers

52

views

Coloring of small chessboards on the torus

recreational-mathematics coloring chessboard

modified 2 hours ago Empy2 46.4k

0

votes

0

answers

34

views

On Integer Sequences

sequences-and-series

asked 2 hours ago Firdous Ahmad Mala 1,029

0

votes

0

answers

29

views

Define homology by simplicial Eilenberg Maclane spectra.

algebraic-topology homotopy-theory stable-homotopy-theory

modified 2 hours ago XT Chen 1,314

1

vote

1

answer

22

views

How to discuss the convergence and divergence of series $\sum_{n=1}^{\infty}(-1)^n \frac{\ln n!}{n^{\alpha}}$?

sequences-and-series convergence-divergence

answered 2 hours ago herb steinberg 11.2k

1

vote

1

answer

24

views

If $g$ is a continuous nonnegative function on $[a,b]$ and if $\int_{a}^{b} g = 0$, then $g$ is identically $0$ on $[a,b]$

real-analysis proof-explanation riemann-integration

modified 2 hours ago Siong Thye Goh 139k

1

vote

0

answers

13

views

A problem on geometry of regualr n-gonal cupolae.

geometry euclidean-geometry

asked 2 hours ago Aryan Anand 11

0

votes

1

answer

16

views

Proving that a space is second countable

general-topology second-countable

answered 3 hours ago Well 28

0

votes

0

answers

11

views

How to solve this question on mixture and alligation?

soft-question arithmetic

asked 3 hours ago Reluctant Metallurgist 41

0

votes

0

answers

15

views

Let $f:[0,2\pi]\rightarrow[-1,1]$ satisfy $f(\theta)=\sum_{r=0}^n(a_r\sin(r\theta)+b_r\cos(r\theta)$ for $a_h,b_i\in R$. If $|f(x)|=1$...

trigonometry

asked 3 hours ago Sunaina 692

0

votes

0

answers

7

views

An LMI transformation problem

convex-optimization linear-control linear-matrix-inequality

asked 3 hours ago LostBird 25

0

votes

0

answers

14

views

Differentiating measure of a submanifold depending on a parameter

real-analysis measure-theory differential-geometry partial-differential-equations calculus-of-variations

modified 3 hours ago Marc 243

0

votes

0

answers

18

views

Example of an inner product space.

functional-analysis hilbert-spaces

asked 3 hours ago A learner 2,798

1

vote

0

answers

79

views

+50

Is there a better form for $\mathrm{\int_0^1 D(x) dx}$ or $\mathrm{\sum_{n=2}^\infty \frac{n\cos(n!)}{n!^2}}$? D(x) is the Darboux fractal function.

special-functions bessel-functions fractals trigonometric-integrals trigonometric-series

modified 3 hours ago Tyma Gaidash 2,758

0

votes

0

answers

22

views

Bisector proof in an olympiad level problem

contest-math euclidean-geometry

asked 3 hours ago auntyellow 211

1

vote

1

answer

16

views

Deformation of Flux or Circulation Integrals.

multivariable-calculus vector-analysis stokes-theorem greens-theorem

answered 3 hours ago peek-a-boo 27.3k

0

votes

1

answer

19

views

Solving least squares equations

statistics least-squares

modified 3 hours ago grand_chat 30.4k

2

votes

0

answers

21

views

Given a prime $p$ and a positive integer $a \not \equiv 0,1 \pmod p$, show that S = $\sum^{p-1}_{i=1} a^i \equiv 0 \pmod p$

elementary-number-theory reference-request primitive-roots

asked 3 hours ago Eric Snyder 808

0

votes

0

answers

17

views

The expected value of a special coin flips game

probability expected-value recreational-mathematics

asked 3 hours ago StochasticC 49

0

votes

0

answers

3

views

CEF, Regression, and Mean Independence Assumption

regression

asked 3 hours ago SimonSaltine 67

0

votes

1

answer

13

views

Whether the below matrices are in row-echelon form / reduced row-echelon form

linear-algebra

answered 3 hours ago LeWoody 135

0

votes

0

answers

9

views

Irreducible polynomial $x^n - P(y)$ in field extension when $P(y)$ is not constant and not has repeated factors

abstract-algebra field-theory galois-theory extension-field irreducible-polynomials

modified 3 hours ago Nkm20 21

3

votes

0

answers

15

views

Polya Enumeration: Generate Configurations off of Cycle Index

combinatorics group-theory symmetry dihedral-groups polya-counting-theory

modified 4 hours ago Shaun 32.2k

0

votes

0

answers

8

views

Effectus theory and the Giry monad

probability-theory category-theory monoidal-categories monads

asked 4 hours ago Richard Southwell 1,025

4

votes

1

answer

343

views

Probability of 1 billion monkeys typing a sentence if they type for 10 billion years

probability probability-theory

answered 4 hours ago lonza leggiera 15.7k

1

vote

0

answers

35

views

+500

Unitary operators, inner products and unit operators with Dirac notation

group-theory representation-theory inner-products adjoint-operators unitary-matrices

modified 5 hours ago BLAZE 7,959

2

votes

0

answers

21

views

Let $H\leq G$ where $H$ is max simple. Prove either $G$ is simple or there exists a minimal normal subgroup $N$ of $G$ such that $G/N$ is simple.

abstract-algebra group-theory normal-subgroups simple-groups maximal-subgroup

modified 5 hours ago Shaun 32.2k

2

votes

0

answers

12

views

Lebesgue Measure of the Image of an Interval

real-analysis measure-theory derivatives lebesgue-measure

asked 5 hours ago Sam Forster 737

0

votes

0

answers

3

views

UMP and non-decreasing Power function

hypothesis-testing

asked 5 hours ago William Ambrose 404

0

votes

0

answers

11

views

Maximizing expected reward for inhomogenous exponential process

probability statistics stochastic-processes calculus-of-variations economics

modified 6 hours ago somebody-cool 1

3

votes

1

answer

50

views

Number of vacuously transitive relations

combinatorics relations

modified 6 hours ago RobPratt 26.5k

3

votes

0

answers

67

views

Computing zillions of digits of the "derangement constant"

calculus algorithms factorial constants

modified 6 hours ago The_Sympathizer 16.7k

0

votes

0

answers

9

views

Orthonormal basis for Bergman Space

orthonormal schauder-basis bergman-spaces

modified 6 hours ago Shreedhar Bhat 593

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