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Questions tagged [tag-removed]

This tag is to be used only when re-tagging highly(!) off-topic questions where none of the actual tags would make sense; all actual tags the questioner has used are removed and something is needed to have some tag, which is enforced by the software, so this tag is used. However note that this tag is also used in the process of moderators deleting tags. Thus a question having this tag does most of the time not mean that somebody found it off-topic.

This tag is to be used only when re-tagging highly(!) off-topic questions where none of the actual tags would make sense; all actual tags the questioner has used are removed and something is needed to have some tag, which is enforced by the software, so this tag is used. However note that this tag is also used in the process of moderators deleting tags. Thus a question having this tag does most of the time not mean that somebody found it off-topic.

For more information about the usage of this tag see also:

346 questions
35
votes
1 answer

Mr. G.P.K.'s questions

WARNING: An acquaintance of mine, Mr.Goosepond Prhklstr Kratchinabritchisitch, has requested permission to post his questions under my username. When I asked him why he didn't do it under his own name, he gave me a convoluted answer of which I…
Georges Elencwajg
  • 46,833
6
votes
3 answers

functions with same area

I have two real valued functions $f_1$ and $f_2$ such that $\int_0^Tf_1=\int_0^Tf_2=a_1$ $\int_0^Tf_1^2=\int_0^Tf_2^2=a_2$ $\forall \\ t, f_1(t),f_2(t)\in[0,1]$ Now,I want to construct a family of functions using $f_1$ and $f_2$ which also have…
ConfuseD
  • 61
6
votes
3 answers

Volume of Minkowski sum of a ball and an ellipsoid

Is there a simple way to calculate/estimate the volume of Minkowski sum of an n-dimensional unit ball and an n-dimensional ellipsoid? Even a simple ellipsoid like $\frac{x_1^2}{a^2} + x_2^2 + \ldots + x_n^2 = 1$ will do.
ben
  • 63
6
votes
1 answer

What's difference between 'functional' and 'function'?

Hi, I want to know difference that between 'functional' and 'function'. Of course, in Wikipedia, http://en.wikipedia.org/wiki/Functional_(mathematics), there is many texts. But what's the simple answer for this question? ;-)
KKH
  • 61
6
votes
1 answer

Odd equidissection of semisquare

Is it possible to cut the quadrilateral (0,0), (1,0), (0,1), (2,2) into an odd number of triangles of the same area?
Paulo Caetano
  • 61
5
votes
4 answers

Integer division: the length of the repetitive sequence after the decimal point

When dividing two integers, there may be an infinite sequence of digits after the decimal point (e.g. in the cases of 1/3, 1/7 etc). As far as I know, if the two numbers divided are integers, this infinite sequence will be, from some point, a…
Rax Olgud
  • 159
5
votes
0 answers

Azimuthal and polar integration of a 3D Gaussian

Numerical evaluation of the following integral of a 3D gaussian $G$ seems to result in a 1D Gaussian $g$: $$\int_{0}^{2\pi}\int_{0}^{\pi}G(R,\phi,\theta)\sin\theta\ \text{d}\theta \ \text{d}\phi= g(R)$$ where the 3D Gaussian in spherical coordinates…
Wox
  • 347
3
votes
2 answers

Jacobian and determinants

Start with variables $(a_1, a_2, a_3, … a_n)$ and transform it to the system $(x_1, x_2, x_3, … x_n)$ where the xi’s are the solutions to $x^n + a_1x^{n-1} + a_2x^{n-2} + a_3x^{n-3} +…+ a_n$. The Jacobian transformation seems to be $da_1 da_2 da_3 ……
Col_Boogie
  • 33
2
votes
0 answers

Computing a double integral

Hi, I was wondering whether there was an explicit formula for the following integral: $$\int_{B_r}\int_{B_r}|x-y|^{-(d-1)} dx dy$$ Here $dx$ and $dy$ is lebesgue measure on $R^d$ and $B_r$ is some ball of radius $r$. I was able to write down an…
ABC
  • 21
2
votes
2 answers

Is there a continuous function on $f:\mathbb{R} \rightarrow \mathbb{R}$ with uncountably infinite turning points?

I was thinking about the statement "if f is continuous on the interval I, there is not necessarily an interval J in I on which f is monotone." and this led me to the question "does there exist a continuous function $f:\mathbb{R} \rightarrow…
Kate
  • 65
2
votes
2 answers

Expressions for the Square of an Integral

Is there a way to simplify the following expression: $\lgroup{\int^A_0 x(s)ds}\rgroup ^2$ I'm looking for an expression that can possibly get rid of the squared term, so that I can have just an integral of the first order.
blackj4ck
  • 23
2
votes
2 answers

What is the mathematical meaning of this symbol?

Someone asked me, and I told them I would try to find out... what is the meaning of this symbol: B'L     or     BL' (I'm not sure if the tick comes before or after the L. It was found on a "nerd clock". The value of this symbol, by the way, is…
fuzzylintman
  • 159
1
vote
0 answers

Fractional Radon - Nikodym derivative

Given $f$ a function measurable in $[0,\infty]$ defined as $$\frac{d\mu}{d\nu}$$ such that, for every measurable set $A$ we have: $$\mu(A)=\int_A{}fd\nu$$ the function $f$ is called $Radon - Nikodym\ derivative$ of $\mu$ respect to $\nu$ My question…
Riccardo.Alestra
  • 399
1
vote
1 answer

integral of a rational function (1+a_i s)^-1/prod((1+a_j s)^k)

Is there any closed-form expression for the following integral: $\int_0^\infty \frac{1}{(1+a_i s) \prod_{j=1}^n (1+a_j s)^k} ds $ where the ai are >0 and k is a positive integer. And, if k is not an integer? Thank you
Jose M Del Castillo
  • 13
1
vote
0 answers

Recursive algorithm for integration of complex functions

Integrals of the form $\int_{0}^{\pi} d\theta \sin\theta f(r(\theta)) j_{\ell_{1}} (a r(\theta))y_{\ell_{2}}(br(\theta))P_{\ell_{3}} ^{m} (\cos(\theta))P_{\ell_{4}} ^{m}(\cos(\theta))$, where $f$ is a $C^{\infty}$ complex function, $\ell_{i}$…
Asterios Gkantzounis
  • 581
  • 5
  • 27
1
2