Inverse Fourier Transform of |k|^2$\lambda$

johnqwertyful
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Homework Statement


\int_{-\infty}^{\infty} |k|^{2\lambda} e^{ikx} dk

Homework Equations


The Attempt at a Solution


As you can guess, this is the inverse Fourier transform of |k|^{2\lambda}. I've tried splitting it from -infinity to 0 and 0 to infinity. I've tried noting that |k| is even, cos is even, sin is odd and getting:

2\int_0^{\infty} |k|^{2\lambda}\cos(kx)dk
But this integral doesn't even converge.
 
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I don't think the original integral converges either, no matter what the value of ##\lambda## is. Try using different values of ##\lambda## and ##x## and integrating numerically with a large interval of integration.
 
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