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    A Psi function or digamma function?

    Hi everyone, concerning serie representation of psi function. In te solution of bessel function of the second kind we have the following expressions for the psi functions psi(m+1) and psi(n+m+1) then they give the series for the two psi functions ie(or digamma function) sum k from 1 to m of...
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    A Question about computing residues after substitution

    Hi, thank you very much for the answer Belgium 12
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    A Question about computing residues after substitution

    Hi members, See attacged PDF file for my question Thank you
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    A Residues of gamma functions

    Hi members, I have a problem with the computation of residues involve the gamma functions. (see attached Pdf file) Can you show me for the first residue with the arrows, or give a hint or a link. Thank you
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    I Series expansions of log()

    Hi, see attached PdF file for my question concerning serie expansion of log(z) at infinity. Thank you Belgium 12
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    I Differentiation notation

    Hi members, see attached PdF file. What's the difference between d/dx and d/d(x^2) I don't understand this notation?? Thank You
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    I Laplace transform using differential equations

    Hello Mark 44, If I understand it,Y'(0)=infinity.Here infinity can be treated as a constant. Thank you
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    I Laplace transform using differential equations

    Hi members, Laplace transform using differential equations.(see attached PDF file) My question d/ds(s^2 y- s Y(0)-Y'(0).)....... Y(t)=sin(sqrt(t)) Y(o)=0 Now Y'= cos(sqrt(t)/2sqrt(t) Y'(0)=infinity d/ds (Y'(0)=?? can it be treated as a constant or can we change limit and...
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    Integrals log x in terms of dilogarithm

    Hi members, see attached PdF file.Have you any idea to prove thes integrals Thank you
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    Substitution in integral

    Hi members, see attached Pdf file. For a<0,write b=-a and let x=bt.Then My question: how becomes the denominator x+a to 1-t??? I don't see it Thank you
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    Gamma function and factorial

    Hi members, gamma (n+1)=n! Now I have the following: gamma(2(n+3/2))=gamma(2n+1) What is factorial notation for this?? Thank you
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    To pwsnafu integral sinh^2(x/2)

    Hi dear members, Sorry for my mistake with coth(x/2). to pwsnafu:I want to integrate integral from -inf to +inf of 1/sinh^2(x/2) Thank you
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    Integral of 1/sinh^2(x/2)

    Hi dear members, I have a problem with the following integral: Integral 1/sinh^2(x/2) from -inf to +inf =-2 coth(x/2) must I consider it as a principal value integral??? Thank you
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    Summation with exponential functions

    Dear members, see attached pdf file.Can you help me to prove this formulas. Thank you Belgium 12 This is not homework.I'm 68 and retired.
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    Fourier transforms

    Hi members, I have a problem with fourier transforms. There are two attached Pdf files. My questions are on the Pdf files.Give me a little help. Thank you Belgium 12
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    Problem with two trigonometric integrals

    Hi I have a little problem with the integrals of the following functions. integral from 0to 2pi ∫sin^2(nθ+ψ)dθ=∫cos^2(nθ+ψ)dθ=pi ψ=the phase angle.They occur in the theory of vibrations. Is it appropriate to set ψ=0 Thank you
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    Fortran Hi,Below is a fortran program to calculate the roots of an

    Fortran Hi, Thanks to Uart for his help.I changed the program with your suggestions and it works fine. Here is the program:! ! Numerical Mathematics and Computing, Fifth Edition ! Ward Cheney & David Kincaid ! Brooks/Cole Publ. Co. ! Copyright (c) 2003. All rights reserved. ! For...
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    Fortran Hi,Below is a fortran program to calculate the roots of an

    Hi, Below is a fortran program to calculate the roots of an equation by newton's method. I compile the program with the free compiler g95: g95 -c newton.f95 then g95 newton.f95 -o newton.exe When I run the program newton.exe I get the error can't assign value INTENT(IN)::x to...
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    Zeros of bessel functions in scilab

    Hi, I use scilab 5.2.2 Ik have a problem to find the zeros or roots of the bessel functions J0,J1... Whel I write besselj(0,3) I get the value of the bessel function Jo(3)=0,2600520. Can someone help me how to find the zeros of these bessel functions in scilab. Thank you kind...
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    Ln(x) < sqrt(x) for 1<x<infinity

    Hi, How can I show or proof: 1) ln(x)<sqrt(x) for 1<x<infinity 2) ln(x)<1/sqrt(x) for 0<x<1 Thank you
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    Complex variables

    Hi, yes you are right. But it's my fault,I forgot something. I have to show this inequalities for z->infinity as a lower and upper bound in a complex integral. Sorry
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    Complex variables

    Hi, I need two simple proofs of complex inequalities. 1) |1-z|/|z|<2 2)|1+z|/|z|>1/2 Ik need them for a bound of a complex integral.It's not homework Thank you
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    Laplace equation

    It's to satisfy the boundary conditions at 0 and pi. solutions are u(x,y)=A exp(ny) + Bexp(-ny) or =a sinh(ny)+bcosh(ny) or =cosh(ny)+cosh n(y-pi) this satisfy thr BC at 0 and pi The laplace equation is invariant under translation belgium 12
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    Complex integral

    Hi, problrm with complex integral.Consider the integral \int_{0}^{\infty}\frac{(x^a-1)}{x^3-1}\,dx use the branch 0<phi<3pi/2 and an idented contour at z=0 and z=1.(circular contour in the upper half plane) a)show that the integral can be written in terms of the integral...
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    LaTeX Use latex

    HI, I start to understand the structure of latex.Icreated my first latex file with an editor. I runned latex on the tex file and I got dvi file.With preview I could see the text in ps or Pdf. It was a downloaded example. Now: 1)I run latex from from the prompt c:\ you click in...
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    LaTeX Use latex

    Hi, thank you very much.I try it out.
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    LaTeX Use latex

    use of latex hi, I have downloaded miktex 2.7(basic) and AMS latex. They are both installed,but how I start the two programs,and write math.expressions. I know maybe it is easy,but for me everything is new. Thanks for your help
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    LaTeX Use latex

    Use of "Latex" Hi, I want to use Latex.I never heard about latex before. If it runs on my computer: 1)Where can I download the files I need. 2)How to install 3)Where can I find the source code for writing the mathematical expressions. My computer: O.S/:Windows...
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    Classification of quadrics

    Hi, mathwonk yes that's.for three variables I think you have to diagonalize the matrix.First you you must compute the eigen-values of the matrix . Thank you for your help.
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    Classification of quadrics

    Hi, What I really mean is: you have a general equation of the second order in three variables and by translations and rotations to remove Xy-Xz and yz terms you transform it to the canonical forms of quadrics.(ellipsoids,hyperboloids,cone......) Bye
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