Problem

2. (15 PTS) Use the accompanying tables of Laplace transforms and properties of Laplace transforms to find the Laplace transform of the function below. Note that an appropriate trigonometric identity may be necessary.
\[
f(t)=e^{-2 t} \sin 2 t+e^{3 t} t^{2}
\]

Answer

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Answer

So, the final answer is \(\boxed{F(s) = \frac{2}{(s+2)^2 + 4} + \frac{2}{(s-3)^3}}\). This is the Laplace transform of the given function.

Steps

Step 1 :Given the function \(f(t)=e^{-2 t} \sin 2 t+e^{3 t} t^{2}\), we are to find its Laplace transform.

Step 2 :Using the table of Laplace transforms, we know that the Laplace transform of \(e^{at}f(t)\) is \(F(s-a)\) and the Laplace transform of \(t^n f(t)\) is \((-1)^n F^{(n)}(s)\).

Step 3 :Applying these rules, the Laplace transform of \(e^{-2 t} \sin 2 t\) is \(\frac{2}{(s+2)^2 + 2^2}\) and the Laplace transform of \(e^{3 t} t^{2}\) is \(\frac{2!}{(s-3)^(2+1)}\).

Step 4 :Adding these two results together, we get the Laplace transform of the function \(f(t)\) as \(F(s) = \frac{2}{(s+2)^2 + 4} + \frac{2}{(s-3)^3}\).

Step 5 :So, the final answer is \(\boxed{F(s) = \frac{2}{(s+2)^2 + 4} + \frac{2}{(s-3)^3}}\). This is the Laplace transform of the given function.

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