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QUESTION

Find the inverse Laplace transform of the function
$\ds\frac{1}{s^2+4}$.

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ANSWER

$\ds{\cal{L}}^{-1}\left\{\frac{1}{s^2+4}\right\}=
{\cal{L}}^{-1}\left\{\frac{\frac{1}{2}(2)}{s^2+2^2}\right\}=
\frac{1}{2}\sin(2t)$




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