Mathematics Stack Exchange

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vote

0

answers

9

views

Implicit partial differentiation along $x$ and $y$

multivariable-calculus partial-derivative

modified 1 min ago Rodrigo de Azevedo 14.9k

0

votes

0

answers

8

views

Losing a curl in vector identity

vectors vector-analysis vector-fields

modified 1 min ago Rodrigo de Azevedo 14.9k

0

votes

2

answers

8

views

$a,b \in R$ a ring. If $a | b$ in $R$ then $bR\subseteq aR$?

abstract-algebra elementary-number-theory ring-theory divisibility

answered 1 min ago John Hughes 74.5k

1

vote

1

answer

8

views

List of relations, union and intersections of relations

discrete-mathematics elementary-set-theory relations

modified 27 secs ago J.-E. Pin 24.9k

0

votes

0

answers

2

views

Cosine sum reduction

trigonometry

asked 2 mins ago Leucippus 21.8k

0

votes

1

answer

41

views

Construct a triangle giving the length of one side, the angle opposite that side and the difference of the remaining sides.

geometry

modified 3 mins ago user 11.8k

0

votes

0

answers

2

views

Check if an integer $N$ can be represtented as multiple of $R$ integers (With a catch)

integers

asked 4 mins ago Srivaths 101

0

votes

0

answers

9

views

$\mathbb Q(\sqrt2)\ncong\mathbb Q(\sqrt3)$ as fields [duplicate]

abstract-algebra solution-verification

asked 4 mins ago George 1,804

-2

votes

0

answers

7

views

find area by picture

geometry discrete-mathematics contest-math triangles least-squares

modified 6 mins ago Shaun 21.9k

0

votes

0

answers

11

views

I am stuck with this problem that I created myself while solving some another problem. Any help would be appreciated

number-theory problem-solving

asked 7 mins ago Developer 1

1

vote

0

answers

7

views

1D wave equation: d'Alembert solution and periodicity

wave-equation

modified 8 mins ago pluton 737

1

vote

1

answer

30

views

If W is a subspace of V and $x \subsetneq W$, prove that there exists $f \in W^0$ such that $f(x) \neq 0$.

linear-algebra dual-spaces

answered 9 mins ago Gracious 98

0

votes

1

answer

17

views

Why can't we choose a simpler bound in this proof?

real-analysis limits solution-verification

answered 9 mins ago David Kipper 1

1

vote

2

answers

13

views

If $Dim L(V,V)$ is finite then $DimV$ is finite?

vector-spaces

answered 10 mins ago Matematleta 20.5k

0

votes

1

answer

9

views

how to get n digits of a given number?

decimal-expansion

answered 10 mins ago Eric Towers 48.1k

3

votes

1

answer

24

views

Of all triangles with a given perimeter, find the triangle with the maximum area. Justify your answer.

calculus geometry optimization

answered 10 mins ago Quanto 29.8k

0

votes

0

answers

8

views

ancient use of stereographic projection

differential-geometry manifolds math-history

modified 12 mins ago joriki 194k

0

votes

0

answers

8

views

Laplace Transforms of ODE

soft-question laplace-transform

modified 13 mins ago Steve Boby George 1

0

votes

1

answer

9

views

Solution verification in this Probability exercise.

probability solution-verification conditional-probability

answered 13 mins ago joriki 194k

0

votes

0

answers

4

views

Proof the formula for the expectation of a log-normal distribution by using taylor expansion

statistics probability-distributions taylor-expansion expected-value

asked 14 mins ago crazybird1 11

0

votes

1

answer

13

views

Check if a vector satisfies a certain equation

matrices vectors

modified 15 mins ago Will Jagy 115k

0

votes

0

answers

6

views

Electrical Circuits Modelling and Formal Proofs

graph-theory

asked 16 mins ago Henrique Inonhe 53

0

votes

1

answer

10

views

Limit of contour integral involving polynomial

complex-analysis residue-calculus

answered 56 secs ago Eric Towers 48.1k

1

vote

0

answers

6

views

Bound for expectation of product of dependent random variables

probability-theory random-variables expected-value cauchy-schwarz-inequality

asked 16 mins ago Dasherman 1,477

0

votes

0

answers

5

views

Find the 'jump' of force of mortality under Balducci assumption

actuarial-science

asked 17 mins ago Helen 55

-1

votes

0

answers

19

views

Check if the following sets are (i) open or closed, (ii) bounded and (iii) compact. Explain

real-analysis

modified 18 mins ago jaspreet 525

0

votes

1

answer

9

views

Is $f(x,y)= 1/x^2$ integrable over $\{(x,y): 0<y<x<1\}$?

integration lebesgue-integral

answered 19 mins ago JustDroppedIn 4,468

3

votes

0

answers

101

views

Local compactness of a product of locally compact spaces

general-topology compactness solution-verification

modified 19 mins ago pluton 737

0

votes

0

answers

23

views

Sum of perfect powers of n natural numbers

sequences-and-series number-theory elementary-number-theory summation perfect-powers

modified 20 mins ago Shagun 37

0

votes

0

answers

17

views

A Mathematical Programming Puzzle

number-theory prime-numbers programming

asked 20 mins ago Gaurav ahlawat 3

0

votes

0

answers

5

views

Help to understand the prove of the maximum principle

analysis harmonic-analysis harmonic-functions

modified 20 mins ago Dexter 57

1

vote

1

answer

14

views

Show that the $n+1$ elementary codewords (of length $2^{n}$ ) are linearly independent (Reed-Muller Codes)

linear-algebra coding-theory reed-muller-codes

answered 21 mins ago J.G 3,875

1

vote

0

answers

17

views

Can you explain the difference between the sphere $S^5$ and the manifold $S^3 \times S^2$?

differential-geometry

modified 22 mins ago KReiser 22.5k

0

votes

0

answers

4

views

Show Bessel integral function is solution of $x^2y''+xy'+(x^2-n^2)y=0$

real-analysis real

asked 22 mins ago Giulia B. 1,039

0

votes

0

answers

5

views

Navier-Stokes uni-dimensional flow and two-dimensional flow equations

pde normed-spaces

asked 23 mins ago Anonymous 1

0

votes

1

answer

18

views

Divergence Formal Definition Meaning of $\lim_{R_{(x,y,z)} \to 0}$ of Region R

limits definition surface-integrals

modified 24 mins ago Paul Sinclair 26k

0

votes

0

answers

8

views

Help with directional derivatives

derivatives

asked 28 mins ago Mathomat55 143

1

vote

0

answers

11

views

Diffeomorphism between circle and square clarification

real-analysis manifolds diffeomorphism

asked 28 mins ago gtoques 568

0

votes

0

answers

25

views

Weak law for dampened Cauchy distribution

real-analysis probability-theory probability-distributions probability-limit-theorems

modified 29 mins ago P. Brown 960

1

vote

0

answers

20

views

Proof of a basic inequality for infinite series

real-analysis sequences-and-series inequality power-series

modified 30 mins ago MathKid 23

0

votes

0

answers

4

views

Question about complex integration over half circle (not closed)

complex-analysis complex-integration residue-calculus cauchy-integral-formula

asked 32 mins ago Hyunmin Hong 33

1

vote

1

answer

24

views

Prove that $\log(x!)$ is $O(x\log x)$

logarithms asymptotics solution-verification factorial

answered 33 mins ago vonbrand 23.1k

0

votes

0

answers

8

views

Probability of Hitting Skeet Shots

probability

asked 33 mins ago wilada 1

0

votes

1

answer

18

views

convergence of $\int_{0}^{\infty} x^{n-1}e^{-x}dx$ (Gamma function)

real-analysis improper-integrals gamma-function

answered 36 mins ago sourisse 736

0

votes

0

answers

13

views

MLE of Normal Distribution and checking if the estimator is unbiased

probability normal-distribution statistical-inference maximum-likelihood

asked 39 mins ago Tony Stark 1

0

votes

0

answers

11

views

At what values of $\alpha$ does $\int\limits_0^1\frac{\arctan(x^2+x^{2\alpha})}{x\ln^\alpha(1+x)}dx$ converge?

calculus integration improper-integrals

asked 39 mins ago Sofia B. Lopez 507

0

votes

0

answers

14

views

Solve differential equation with square

ordinary-differential-equations

asked 39 mins ago mkultra 771

0

votes

0

answers

9

views

Prove that a given line is a horizontal asymptote for a given function

real-analysis calculus solution-verification

modified 42 mins ago uniquesolution 13.2k

1

vote

1

answer

18

views

Divisibility of Coefficient Related to Cyclotomic Integer

elementary-number-theory polynomials divisibility cyclotomic-polynomials

modified 45 mins ago Larry Freeman 7,402

0

votes

1

answer

22

views

How do I find an area as a function of only x?

calculus functions area

answered 45 mins ago uniquesolution 13.2k

1

vote

0

answers

27

views

What does it mean to say that a point at infinity is mapped to $0$?

transformation projective-geometry projective-space

modified 48 mins ago geraldo altier 143

1

vote

2

answers

49

views

Probability of Independent Normal Random Variables

probability probability-distributions conditional-probability

answered 51 mins ago jose 11

0

votes

0

answers

8

views

Why are -/+0.5 scale divisions used in continuity corrections for binomial approximation to normal distribution?

statistics probability-distributions normal-distribution approximation binomial-distribution

modified 51 mins ago XXb8 109

0

votes

1

answer

40

views

Sum of perfect powers

sequences-and-series number-theory summation perfect-powers

answered 52 mins ago Kieren MacMillan 5,586

0

votes

0

answers

8

views

Can multiple-operation algebraic structures be graphically organised thusly?

abstract-algebra

asked 53 mins ago gen-z ready to perish 5,749

0

votes

0

answers

7

views

The generality of “neusis plus”

geometry polynomials geometric-construction

asked 53 mins ago Parcly Taxel 57.5k

0

votes

0

answers

7

views

From Langevin to Fokker-Plank equation

stochastic-processes

asked 54 mins ago user314849 81

0

votes

0

answers

13

views

proving bi-Lipschitz function has an inverse that is a Lipschitz function

real-analysis continuity proof-writing metric-spaces inverse

modified 58 mins ago mq1998 167

0

votes

0

answers

6

views

Quotient with third order polynomial infinity as denominator confusion.

limits infinity expression-simplification

modified 1 hour ago Charlie Cockerell 1

0

votes

0

answers

11

views

Estimating a sum of cosines related to random walk on $\mathbb{Z}_{n}^{n}$

trigonometry inequality asymptotics random-walk spectral-graph-theory

asked 1 hour ago Austin80 106

-1

votes

0

answers

7

views

Probabilty adjusting standard deviation

standard-deviation

asked 1 hour ago hoese 1

0

votes

0

answers

25

views

Show that $[\bar{\mathbb Q}:\mathbb Q]=\infty$

abstract-algebra field-theory solution-verification

modified 1 hour ago user26857 41.1k

1

vote

0

answers

8

views

Veblen fixed point theorem: how does sequence of differences from repeated application behave?

set-theory ordinals

asked 1 hour ago KJJ 143

2

votes

0

answers

8

views

Can the calculus of variations be used to optimize to a constraint that the desired function must pass through specific intermediate points?

optimization calculus-of-variations

modified 1 hour ago The_Sympathizer 14.3k

0

votes

0

answers

5

views

Borel action and stabilizer map

group-theory measure-theory

asked 1 hour ago Mariah 3,453

0

votes

0

answers

18

views

Why does the Lebesgue Integral need to be defined for only non-negative functions?

definition lebesgue-integral

asked 1 hour ago BENG 527

0

votes

0

answers

8

views

intersection of four linear equation

linear-algebra

asked 1 hour ago Samar Imam Zaidi 4,004

0

votes

0

answers

13

views

for which values of a is the matrix not diagonalizable

linear-algebra

asked 1 hour ago bruh 3

0

votes

0

answers

17

views

conditional expectation of partial sum process

probability probability-theory conditional-probability

modified 1 hour ago Rob Pratt 10.5k

1

vote

0

answers

14

views

Find a hamiltonian path in $T^{3}$

graph-theory trees hamiltonian-path

modified 1 hour ago Rob Pratt 10.5k

0

votes

0

answers

12

views

Engel Expansion Algorithm question

real-analysis sequences-and-series convergence-divergence real-numbers

modified 1 hour ago Sebastian Cor 272

1

vote

3

answers

31

views

If a,b,c $\in[0,\frac{\pi}{2}]$,and $\cos a=\tan b,\cos b=\tan C,\cos c=\tan a,$ prove that $\sin a=\frac{\sqrt 5-1}{2}$.

trigonometry proof-explanation

answered 1 hour ago Quanto 29.8k

0

votes

0

answers

10

views

strong maximum principle for subharmonic functions

analysis functions harmonic-functions maximum-principle

modified 1 hour ago Rob Pratt 10.5k

0

votes

0

answers

18

views

Find the points of relative extrema of $f(x)=x^x$

calculus maxima-minima

asked 1 hour ago Aristotle Stagiritis 361

0

votes

0

answers

14

views

Expected value of a Markov chain

stochastic-processes markov-chains

modified 1 hour ago Rob Pratt 10.5k

1

vote

0

answers

8

views

Linear map and polynomials

linear-transformations

asked 1 hour ago user638057 671

2

votes

0

answers

8

views

A problem in my solution: find a polynomial $P(x)$ such that the derivative of $e^{-x^2}P(x)$ equals $0$ for $x=0$, $x=\pm a$ and $x=\pm b$.

polynomials solution-verification

asked 1 hour ago windingnumberone 573

0

votes

0

answers

3

views

Cone of feasible directions

optimization nonlinear-optimization convex-cone

asked 1 hour ago measurehell 159

1

vote

1

answer

49

views

How to check completeness of a statistic of a continuous variable?

statistics measure-theory statistical-inference

answered 1 hour ago Dani 11

0

votes

0

answers

16

views

Motivation for studying Operator $K_1$

c-star-algebras k-theory

modified 1 hour ago sirjoe 655

3

votes

0

answers

18

views

Embedding Sobolev $H^1$ into $L^\infty$ space

complex-analysis functional-analysis sobolev-spaces integral-inequality

modified 1 hour ago DuFong 827

0

votes

0

answers

6

views

Reference for classification of Irreducible $\mathfrak{sp}(n,\mathbb{R})$-modules

reference-request lie-algebras

asked 1 hour ago María Alejandra 1

1

vote

0

answers

8

views

Every non-zero spectral value of a compact operator is an eigenvalue

functional-analysis banach-spaces spectral-theory

asked 1 hour ago Sebpar 23

0

votes

0

answers

7

views

Signature of a Matrix

matrices eigenvalues-eigenvectors

asked 1 hour ago John Doe 37

1

vote

3

answers

24

views

confused with algebraic derivation used for arriving at the equation n*(n+1)/2

algebra-precalculus

answered 1 hour ago fleablood 93.6k

0

votes

0

answers

8

views

Diffusion Differential Equations stability values

pde

modified 1 hour ago gt6989b 43.6k

1

vote

1

answer

19

views

two shooters, probabilities that have a possibility of going to infinity

probability

answered 1 hour ago dm63 179

0

votes

0

answers

10

views

What form must this function in this integral take?

integration complex-analysis definite-integrals fluid-dynamics

asked 2 hours ago Jay Lemmon 1,503

1

vote

0

answers

23

views

Big-O notation, equality

real-analysis asymptotics

modified 2 hours ago Mohamed Ali 587

0

votes

0

answers

7

views

Analytic semigroup on L^p

operator-theory generating-functions semigroups semigroup-of-operators

asked 2 hours ago Newinmaths 43

0

votes

0

answers

10

views

Why is the Fourier Transform of sin(2pi(t-1))/(pi*t-1)) e^(2w)?

fourier-transform

asked 2 hours ago Formeanlegion 1

2

votes

0

answers

14

views

Does Lebesgue Change of Variables only hold for Borel functions?

real-analysis measure-theory lebesgue-measure

modified 2 hours ago Keefer Rowan 626

1

vote

0

answers

12

views

Solving a differential equation using substitution - steps verification

calculus ordinary-differential-equations

modified 2 hours ago Aryadeva 19k

5

votes

0

answers

104

views

+50

Lévy's metric on $\mathbb{R}^d$

real-analysis probability probability-theory measure-theory weak-convergence

modified 2 hours ago mathex 595

1

vote

0

answers

4

views

How to solve non linear integro-differential equation

laplace-transform convolution integro-differential-equations

modified 3 hours ago Andrew Ostergaard 4,710

4

votes

1

answer

22

views

Modifying circulant Latin Squares

matrices algorithms trace latin-square circulant-matrices

modified 3 hours ago Yong Hao Ng 4,867

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