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wxstall
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Evaluating a "Fourier Transform" Integral
Evaluate
I = ∫[0,∞] e-ktw2 cos(wx) dw
in the following way: Determine ∂I/∂x, then integrate by parts.
Possibly?
Since integral limits do not depend on x, the partial with respect to x should simply be:
I = ∫[0,∞] e-ktw2 cos(wx) (-w) dw
The integration by parts poses the main problem. I have done a change of variables allowing z = w2, although it seems I will have a recursion issue with an extra integral that is unable to be evaluated after each integration by parts.
For integration by parts, I previously let u = sin(x√z) and dv = e-ktzdz but this doesn't seem to lead anywhere good.
I considered using Euler's formula to replace the cosine but this seems to lead in the wrong direction also.
Any suggestions are appreciated. Thanks!
Homework Statement
Evaluate
I = ∫[0,∞] e-ktw2 cos(wx) dw
in the following way: Determine ∂I/∂x, then integrate by parts.
Homework Equations
Possibly?
The Attempt at a Solution
Since integral limits do not depend on x, the partial with respect to x should simply be:
I = ∫[0,∞] e-ktw2 cos(wx) (-w) dw
The integration by parts poses the main problem. I have done a change of variables allowing z = w2, although it seems I will have a recursion issue with an extra integral that is unable to be evaluated after each integration by parts.
For integration by parts, I previously let u = sin(x√z) and dv = e-ktzdz but this doesn't seem to lead anywhere good.
I considered using Euler's formula to replace the cosine but this seems to lead in the wrong direction also.
Any suggestions are appreciated. Thanks!