Inverse Laplace Transform: How to Manipulate Fractions for Completing the Square

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TyErd
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Homework Statement


Find the inverse laplace transform of [itex]\frac{3s + 7}{s^{2} - 2s + 10}[/itex]

Homework Equations


completing the square.
[itex]e^{at}sin(bt) = \frac{b}{(s-a)^{2} + b^{2}}[/itex]
[itex]e^{at}cos(bt) = \frac{s-a}{(s-a)^{2} + b^{2}}[/itex]

The Attempt at a Solution


F(s)= [itex]\frac{3s + 7}{s^{2} - 2s + 10}[/itex]
F(s) = [itex]\frac{3s + 7}{(s-1)^{2} +9}[/itex]
F(s) = [itex]\frac{3s}{(s-1)^{2} +9} + \frac{7}{(s-1)^{2} +9}[/itex]

after this i don't know how to manipulate the first fraction to fit the cosine equation. I know the 3 can be taken up front and a=1 and b=3 I am pretty sure when comparing with the cosine equation but there the problem of making s into s-1.
 
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Don't you have the shifting theorems? Like$$
\mathcal L e^{at}f(t) = \mathcal L(f(t))|_{s \to s-a}$$