Laplace transform of cos(ωt) is s s2 + ω2The

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Laplace transform of cos(ωt) is s
s² + ω²

The laplace transform of e^–2t cos(4t) is

1. s - 2
  (s - 2)² + 16
2. s + 2
  (s - 2)² + 16
3. s - 2
  (s + 2)² + 16
4. s + 2
  (s + 2)² + 16

Correct Option: D

We know that if L{f(t)} = F(s)
Then L{e^at f(t)} = F(s – a)

∴ L[e^-2t cos 4t ] =	s + 2
	(s + 2)² + 4²

=	s + 2
	(s + 2)² + 16