help..solve this by using laplace transform cos4t e5t.....

[dollyme]

:-|how to solve this by using laplace transform cos4t e^5t.....

 

[Deleted member 4993]

:-|how to solve this by using laplace transform cos4t e^5t.....

What do you mean by solve?

Generally, ODEs are solved with Laplace transform.

What you have written is an "expression" - nothing to solve there!!

 

[HallsofIvy]

Solve what "using the Laplace transform" of that function?

If you mean just "find the Laplace transform of \(\displaystyle f(t)= cos(4t)e^{5t}\)" use the definition of the Laplace transform: \(\displaystyle \int_0^\infty cos(4t)e^{5t}e^{-st}dt= \int_0^\infty cos(4t)e^{(5-s)t}dt\)

That integral can be done using "integration by parts"- twice.