Anyone has any idea how to perform the Fourier transform in this case? I'm pretty new to the subject....
$$ f(t) = t^2 e^{-5|t|}$$
Anyone has any idea how to perform the Fourier transform in this case? I'm pretty new to the subject....
$$ f(t) = t^2 e^{-5|t|}$$
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$$ \int_{-\infty}^{\infty}t^2 e^{-5|t|}e^{-ixt}dt = -\frac{d^2}{dx^2}\int_{-\infty}^{\infty}e^{-5|t|}e^{-ixt}dt \\ = -\frac{d^2}{dx^2}\left[\int_{-\infty}^{0}e^{5t}e^{-ixt}dt+\int_{0}^{\infty}e^{-5t}e^{-ixt}dt\right] \\ = -\frac{d^2}{dx^2}\left[\frac{1}{5-ix}+\frac{1}{5+ix}\right] \\ = -\frac{d^2}{dx^2}\left[\frac{10}{25+x^2}\right] $$