Exploring Fourier Transforms and Integrability for Different Functions

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The discussion focuses on proving that the function f(x) = (1 + |x|)^{-a} is the Fourier transform of an integrable function on R when a > 1, with the condition for convergence of the inverse transform being that the denominator must have a power greater than 1. When 0 < a <= 1, the function fails to meet this condition, indicating it is not integrable. The function f(x) = 1/(log(|x|^2 + 2)) is also questioned regarding its integrability and Fourier transform properties. Participants express uncertainty about formalizing their arguments and seek assistance with the concepts. The conversation emphasizes the importance of understanding integrability conditions in Fourier transforms.
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prove that f(x) = (1 + |x|)^{-a} is the Fourier transform of some integrable function on R, when a > 1. what happens when 0 < a <= 1? how about the function f(x) = 1/(log(|x|^2 + 2))?
 
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Is this homework? If so, what have you done so far?
 
yes, and i realize that we want the integral to converge when we take the inverse transform. so in order to do that, I'm guessing the denominator has to have a power > 1, which is why we have that condition on a. so it will fail the second time, i guess. but i can't formalize my argument (and I'm clueless about the third one).

sry :(
 
any help please? :(
 

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