The Laplace transform of $e^{i5t}$ where $i=\sqrt{-1}$, is

1. $\dfrac{s-5i}{s^2-25} \\$
2. $\dfrac{s+5i}{s^2+25} \\$
3. $\dfrac{s+5i}{s^2-25} \\$
4. $\dfrac{s-5i}{s^2+25}$