Help with Fourier transform of T'(x)/x

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geetar_king
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Homework Statement



[tex]T(x,t)[/tex]

What is the Fourier transform of
[tex] \frac{1}{x}\frac{\partial T}{\partial x}[/tex]

[tex] F(\frac{1}{x}\frac{\partial T}{\partial x}) = \int^{\infty}_{-\infty} \frac{1}{x}\frac{\partial T}{\partial x} e^{i \theta x}dx = ??[/tex]

Homework Equations


The Attempt at a Solution



Can this be split up using convolution into...

[tex]F(\frac{1}{x}\frac{\partial T}{\partial x}) = F(\frac{1}{x})F(\frac{\partial T}{\partial x}) =\int^{\infty}_{-\infty} \frac{1}{x} e^{i \theta x}dx \int^{\infty}_{-\infty} \frac{\partial T}{\partial x} e^{i \theta x}dx[/tex]
 
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You will need to prove that the convolution of 1/x and dT/dx is (1/x)(dT/dx).
 
Okay thanks. I was trying to solve
[tex] \frac{\partial^{2}T}{\partial x^{2}} + \frac{1}{x}\frac{\partial T}{\partial x} = \frac{1}{\alpha}\frac{\partial T}{\partial t}<br /> [/tex]

for [tex] 0 < x < \infty [/tex] and initial condition like [tex] T(x,0) = g(x) [/tex]
with boundary conditions [tex] T(\infty,t) = C_{1} [/tex] and [tex] T(0,t) = f(t)[/tex]

I got stuck with separation of variables and method of characteristics so I was going to try Fourier method