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Lemma used to prove $\left|HK\right|=\frac{\left|H\right|\left|K\right|}{\left|H \cap K\right|}$

group-theory set-partition

modified 1 min ago 45465 609

0

votes

1

answer

18

views

Minimum value of |z| for the locus of a complex number z

algebra-precalculus complex-numbers

answered 4 mins ago Buraian 2,292

0

votes

1

answer

14

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A question of connectedness of subspace

general-topology

answered 5 mins ago TheSilverDoe 13.1k

0

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0

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6

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asked 6 mins ago mike123abc 123

0

votes

0

answers

15

views

How to find a useful variable change for this integral

integration multivariable-calculus

modified 6 mins ago Bernard 157k

1

vote

1

answer

13

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[Literature Request]: Counter factual estimation and modelling

probability reference-request book-recommendation mathematical-modeling bayesian

modified 6 mins ago Albert Steppi 2,564

0

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0

answers

7

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calculate size of sample to reach wanted probability

probability binomial-distribution cumulative-distribution-functions

modified 6 mins ago Bernard 157k

0

votes

1

answer

12

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A single die is rolled 7 times. What is the probability that a six is rolled exactly once, if it is known that at least one six is rolled?

probability probability-theory

answered 7 mins ago zugzug 3,985

0

votes

1

answer

10

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logic

answered 8 mins ago Noah Schweber 178k

0

votes

1

answer

15

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power-series uniform-convergence

answered 11 mins ago Robert Israel 391k

2

votes

2

answers

49

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measure-theory

answered 11 mins ago Ruy 1,751

0

votes

0

answers

16

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Notation for directional derivative

multivariable-calculus notation vector-analysis

modified 12 mins ago psidaga 467

0

votes

1

answer

23

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polynomials numerical-methods interpolation

modified 12 mins ago Ian 81.1k

0

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1

answer

9

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Euler characteristic of a metrized line bundle

abstract-algebra number-theory algebraic-geometry arithmetic-geometry

answered 13 mins ago Nicolas Hemelsoet 7,277

0

votes

0

answers

8

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optimization algorithms exponential-function

modified 14 mins ago Yanqi Huang 101

0

votes

1

answer

9

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Intersection of convex cones

linear-algebra convex-geometry

modified 20 mins ago Heroshizen 137

0

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0

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10

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Hölder function

real-analysis probability holder-inequality

asked 23 mins ago AliceRG 11

2

votes

1

answer

27

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Computing adjoint of differentiation operator

functional-analysis operator-theory hilbert-spaces lp-spaces unbounded-operators

modified 23 mins ago Peter Melech 3,850

0

votes

0

answers

9

views

differential equations with brownian motion

stochastic-calculus brownian-motion stochastic-differential-equations

modified 23 mins ago huighlh 123

1

vote

2

answers

30

views

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elementary-number-theory prime-numbers

modified 24 mins ago Daniel Fischer♦ 190k

0

votes

0

answers

16

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Is injectivity of a set to its hereditary size set preserved in this relative constructible model of ZF-Reg.?

set-theory first-order-logic

modified 26 mins ago Zuhair 2,355

0

votes

0

answers

9

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Derivative of exponential tensor with respect to a vector

linear-algebra matrix-equations matrix-calculus tensors matrix-exponential

asked 26 mins ago yeahyeah 451

1

vote

0

answers

5

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abstract-algebra ring-theory modules examples-counterexamples

asked 28 mins ago paruru 115

2

votes

1

answer

13

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sum of CDF and derivation

probability probability-theory

modified 29 mins ago Eungik Lee 21

2

votes

1

answer

43

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Uniform convergence of $p$-norms

functional-analysis norm lp-spaces uniform-convergence

modified 30 mins ago Matematleta 22.6k

0

votes

0

answers

23

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Help with understanding the definition of a Hodge groupoid

algebraic-geometry flatness groupoids

modified 30 mins ago KReiser 31.3k

1

vote

1

answer

18

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How does I find a generation set of multiplicative group of integers modulo $n$ when: 1. $n $ is prime, and 2. $n $ is not prime?

abstract-algebra group-theory finite-groups modular-arithmetic combinatorial-group-theory

modified 31 mins ago Shaun 25.5k

3

votes

0

answers

23

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linear-algebra least-squares linear-regression

modified 31 mins ago Zhanxiong 10.8k

0

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0

answers

3

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diagonalization covariance maximum-likelihood parameter-estimation fisher-information

asked 33 mins ago youpilat13 65

2

votes

0

answers

17

views

+50

How to check if a graph is biplanar (thickness =2)?

combinatorics graph-theory

modified 38 mins ago RAH 42

1

vote

0

answers

48

views

Prove that intersection of at least a pair of 3-member sets of {1, 2, …, n} is equal to one.

combinatorics elementary-set-theory graph-theory extremal-combinatorics

modified 38 mins ago RobPratt 17.1k

44

votes

4

answers

24k

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Why does the median minimize $E(|X-c|)$?

probability-theory probability-distributions expected-value median

modified 39 mins ago grand_chat 26.4k

0

votes

1

answer

12

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Given a $k$-partite graph $G$ formed from the union of a set of $k$-cliques, is $G$ a comparability graph?

graph-theory order-theory simplicial-complex

modified 40 mins ago Misha Lavrov 75.6k

4

votes

0

answers

56

views

+50

Has this energy a maximum in $B$?

functional-analysis hilbert-spaces banach-spaces spectral-theory

modified 42 mins ago Filippo Giovagnini 1,530

0

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0

answers

5

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Inequality between limits of measures

measure-theory lebesgue-measure

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0

votes

0

answers

5

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odds ratio logistic regression

logistic-regression

asked 44 mins ago Proababilty 141

3

votes

1

answer

43

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Solve $f'^2(x)(x^2 + f^2(x)) = s x (x f'^2(x) -x - 2 f(x) f'(x))$

real-analysis calculus

modified 44 mins ago Raffaele 16.5k

0

votes

0

answers

12

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inequality convex-analysis laplace-transform

modified 45 mins ago LinAlg 14.5k

0

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0

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12

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functional-analysis partial-differential-equations regularity-theory-of-pdes parabolic-pde

modified 47 mins ago Arctic Char 5,620

0

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0

answers

3

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$h$-vector of Standard graded Cohen-Macaulay algebra over a field

cohen-macaulay hilbert-polynomial graded-algebras

asked 47 mins ago uno 822

0

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0

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9

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Show that $\left\{\mathbb R^d\ni x\mapsto e^{{\rm i}\langle t,\:x\rangle}:t\in\mathbb R^d\right\}$ is separating (Stone-Weierstrass)

probability-theory measure-theory exponential-function compactification

modified 50 mins ago 0xbadf00d 10.7k

-1

votes

0

answers

13

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Physical economic argument

economics

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10

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Laplace Equation on Infinite Strip - Value at Infinity

partial-differential-equations solution-verification harmonic-functions boundary-value-problem

modified 56 mins ago superckl 563

2

votes

0

answers

19

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Determining the probability of winning a series of 7 given probability 0.6 of winning each game.

probability probability-distributions binomial-distribution

modified 57 mins ago SprNtndoChlmrs 486

0

votes

3

answers

16

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Is the location parameter always equal to $\operatorname{E}(X)$?

probability probability-theory

modified 58 mins ago Victor 1,458

0

votes

1

answer

23

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Badly Conditioned Matrix Error - Should I concern myself with it?

numerical-methods condition-number

answered 1 hour ago MischiefManaged 1

1

vote

0

answers

23

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Convergence of the integral $\int_0^{\infty}\frac{x\sin(tx)}{k^2+x^2}\,dx$

calculus integration improper-integrals

asked 1 hour ago e2525 63

1

vote

1

answer

21

views

Prove that $\vert P\cap N\vert = p^b$ and $\vert PN/N\vert=p^{a-b}$

group-theory prime-numbers normal-subgroups group-isomorphism

answered 1 hour ago Haran 5,934

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votes

0

answers

17

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If $f \in V^*$, $f(\alpha) = \beta^T\alpha$ for some $b \in V$ then $\|f\| = \|\beta\|$

linear-algebra normed-spaces

modified 1 hour ago Elan Mehl 13

0

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0

answers

13

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discrete math and prove

discrete-mathematics

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2

votes

1

answer

16

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Find transpose of an endomorphism.

linear-algebra dual-spaces transpose

answered 1 hour ago mathcounterexamples.net 43.8k

0

votes

0

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25

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If $P = \{p|~p$ is prime$\}$, such that $\sum_P\frac{1}{p} > 1$, find the maximum natural $n$ for which $\sum_P\Big\lfloor \frac{n}{p}\Big\rfloor < n$

elementary-number-theory inequality prime-numbers

modified 1 hour ago D. Petrov 345

2

votes

0

answers

9

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Conceptual Question About (Extrinsic?) Curvature

geometry differential-geometry manifolds curvature

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vote

0

answers

7

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Dependent Joint Distributions

bivariate-distributions

modified 1 hour ago mathematicianMan 11

1

vote

0

answers

14

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Square Image Of Symbo (⊏) As Used by Barendregt in “The Lambda Calculus - Its Syntax and Semantics”

notation lambda-calculus

asked 1 hour ago David Lloyd 11

0

votes

0

answers

21

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Characterize $Span(ADA^T)$

linear-algebra matrices matrix-calculus matrix-decomposition

modified 1 hour ago Apprentice 90

3

votes

6

answers

198

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Proving that, for an acute $\triangle ABC$, $\sin A + \sin B+\sin C\gt \cos A+\cos B+\cos C$

trigonometry euclidean-geometry triangles

modified 1 hour ago DinosaurEgg 3,886

0

votes

0

answers

16

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On the number of facets of subcomplexes of Shellable simplicial complex

commutative-algebra simplicial-complex algebraic-combinatorics hilbert-polynomial

modified 1 hour ago strat 9

0

votes

0

answers

15

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Calculate distance (in percentage) from street given the current location of the house

percentages

modified 1 hour ago Alexander Solonik 137

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vote

0

answers

16

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Poisson Process - Finding probabilities

probability stochastic-processes poisson-process

modified 1 hour ago The Mathemusician 11

0

votes

0

answers

18

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Number of possible rectangles in a grid using combinatorics

combinatorics geometry

asked 1 hour ago Mafalda Hopkirk 1

1

vote

0

answers

10

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How do I find $\displaystyle {\inf\limits_{n,m} \dfrac {\deg (m)} {\deg (r)}}\ ?$

abstract-algebra ring-theory gaussian-integers euclidean-domain

asked 1 hour ago Anacardium 740

1

vote

0

answers

17

views

Prove without using a truth table that $(p \land q) \rightarrow (p \rightarrow q)$

discrete-mathematics

asked 1 hour ago george.zrs 519

0

votes

0

answers

11

views

How to glue the integral closures of the affine pieces in an integral scheme (Hartshorne II.3.8)?

algebraic-geometry schemes affine-schemes

asked 1 hour ago Redundant Aunt 10.3k

0

votes

0

answers

19

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Minimum $\Re$ on the circle

complex-analysis cauchy-integral-formula

modified 1 hour ago develarist 481

1

vote

1

answer

21

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Finding the norm of this operator

functional-analysis linear-transformations operator-theory

modified 1 hour ago N. S. 121k

0

votes

1

answer

28

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Iterative method proof

numerical-methods

modified 1 hour ago ekkilop 1,938

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votes

0

answers

10

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number-theory analytic-number-theory analytic-continuation

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votes

0

answers

6

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statistics

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0

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6

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General Inequality for Convex Functions

calculus inequality parametrization convexity-inequality

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vote

0

answers

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matrices matrix-decomposition

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1

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0

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26

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Counting “cardinality” of bounded subsets

general-topology set-theory

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3

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2

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real-analysis integration

modified 1 min ago Quanto 42.8k

0

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0

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modified 1 hour ago statscorr 1

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0

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intersection of two quadrics in $\mathbb{P}^4$ contains a del Pezzo surface

algebraic-geometry surfaces

asked 1 hour ago Cornelius 425

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integration analysis

asked 1 hour ago Hiep 113

0

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0

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differential-geometry curves parametrization

modified 1 hour ago Darsen 1,907

1

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4

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80

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Does $\sum_{n=1}^\infty \frac{\sqrt[n]e-1}{n}$ converge?

calculus sequences-and-series convergence-divergence

modified 2 hours ago Integrand 7,222

0

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0

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algebraic-geometry surfaces

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limits asymptotics fourier-transform

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general-topology algebraic-topology manifolds differential-topology manifolds-with-boundary

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fourier-analysis fourier-transform

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complex-analysis

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integration discrete-mathematics machine-learning signal-processing

modified 2 hours ago RTn Saberpour 11

1

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abstract-algebra geometry algebraic-geometry

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1

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25

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calculus differential-topology diffeomorphism stereographic-projections

modified 2 hours ago K.defaoite 3,710

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similarity symmetric block-tridiagonal matrix

linear-algebra matrices numerical-linear-algebra symmetric-matrices similar-matrices

modified 2 hours ago Majed Hamadi 31

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algebraic-geometry divisors-algebraic-geometry

asked 2 hours ago Nathan Lowry 173

0

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tensor-products tensors electromagnetism

modified 2 hours ago Dis-integrating 1,978

0

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Can the line integral be induced by a measure?

real-analysis measure-theory

answered 2 hours ago supinf 9,698

0

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0

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Question12.3 Introduction to analytic number theory

number-theory analytic-number-theory zeta-functions

asked 2 hours ago Ben 1,050

0

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1

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22

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Using the mean value theorem to prove that a non-zero continuous function is only defined at one point when mulltiplied by the dirac delta function

dirac-delta

answered 2 hours ago BlockFace 11

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tensor-products tensors electromagnetism special-relativity

asked 3 hours ago Dis-integrating 1,978

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differential-geometry partial-differential-equations riemannian-geometry heat-equation

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linear-algebra vector-spaces projection

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