I had a maths exam last Monday and the only question I couldn't do is below. Can anyone shed any light?

Laplace transform the following:

1/(s^2+s+5/4)

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- May 25th 2008, 05:55 AMboabMy curiosity needs satisfying
I had a maths exam last Monday and the only question I couldn't do is below. Can anyone shed any light?

Laplace transform the following:

1/(s^2+s+5/4) - May 25th 2008, 06:06 AMgalactus
Don't you mean the inverse LaPlace?.

In that event, $\displaystyle \frac{sin(t)}{\sqrt{e^{t}}}$ - May 25th 2008, 08:21 PMChris L T521

Inverse Laplace:

$\displaystyle \mathcal{L} ^{-1} \left\{\frac{1}{s^2+s+\frac{5}{4}}\right\}$

$\displaystyle \implies \mathcal{L}^{-1} \left\{\frac{1}{\left(s^2+s+\frac{1}{4}\right)+\fr ac{5}{4}-\frac{1}{4}}\right\}$

$\displaystyle \implies \mathcal{L}^{-1} \left\{\frac{1}{\left(s+\frac{1}{2}\right)^2+1}\ri ght\}$

Apply the first translation theorem:

$\displaystyle \implies \mathcal{L}^{-1} \left\{\frac{1}{\left(s+\frac{1}{2}\right)^2+1}\ri ght\}$

$\displaystyle \implies f(t)=e^{-\frac{1}{2}t}\sin\left(t\right)$

$\displaystyle \implies \color{red}\boxed{f(t)=\frac{\sin\left(t\right)}{\ sqrt{e^t}}}$