Question

Laplace transforms problem sin3t+cos3t

Answer 1

have you got a table setup?

Answer 2

otherwise its just a matter if integrateing a by parts with e^(-st)

Answer 3

\[\large\int sin(at)~e^{-st}~dt\]
sin(at) -e^(-st)/s
a cos(at) dt e^(-st) dt

\[\large -\frac{1}{s}e^{-st}~sin(at)+\frac{a}{s}\int cos(at)~e^{-st}~dt\]
cos(at) -e^(-st)/s
-a sin(at) dt e^(-st) dt

etc ...

Answer 4

at 0 and infinity i believe that first term goes zero .....

Answer 5

someone help me with this please

Answer 6

\[\mathcal L\Big\{\sin (nt)\Big\}(s)=\frac{n}{s^2+n^2}\]
\[\mathcal L\Big\{\cos (nt)\Big\}(s)=\frac{s}{s^2+n^2}\]

Answer 7

please do not post your own question into someone elses post .... butyes, someone can help with that