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\begin{exerciseStatement}
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Explain how to solve the following IVP.
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\[ -3 \, {y''} = 18 \, {y} - 15 \, {y'} - 6 \, \delta\left(t - 3\right) \hspace{2em}
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y(0)= 0 ,
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y'(0)= 4 \]
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Hint: \( \frac{1}{s^{2} - 5 \, s + 6} = -\frac{1}{s - 2} + \frac{1}{s - 3} \).
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\end{exerciseStatement}
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\begin{exerciseAnswer}
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\[
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\mathcal{L}\{y\}= \frac{2 \, e^{\left(-3 \, s\right)}}{s^{2} - 5 \, s + 6} + \frac{4}{s^{2} - 5 \, s + 6} \]\[
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\mathcal{L}\{y\}= -\frac{2 \, e^{\left(-3 \, s\right)}}{s - 2} + \frac{2 \, e^{\left(-3 \, s\right)}}{s - 3} - \frac{4}{s - 2} + \frac{4}{s - 3} \]\[ {y} = 2 \, e^{\left(3 \, t - 9\right)} \mathrm{u}\left(t - 3\right) - 2 \, e^{\left(2 \, t - 6\right)} \mathrm{u}\left(t - 3\right) + 4 \, e^{\left(3 \, t\right)} - 4 \, e^{\left(2 \, t\right)} \]
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\end{exerciseAnswer}
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