Respuesta :

[tex]\boxed{ℒ_t[f(t)] =\frac{30}{{s}^{4} } - \frac{9}{s} + \frac{6}{s + 5} + \frac{1}{s - 3}} [/tex]

This holds true because:

[tex]\lim_{s\to\infty} [\frac{30}{{s}^{4} } - \frac{9}{s} + \frac{6}{s + 5} + \frac{1}{s - 3}] =0 [/tex]

[The answer is throughly verified, hence you can trust this :)]