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Signals and Systems - Engineering

Q1:

which is the Laplace transform of x(t) = -e2t ∪(t) ⊕ t ∪(t)?

A

B

C

D

ANS:B -

u(t)-->0 to infinite.

e^2t u(t)*t u(t).

[
t u(t)=d[u(t)]/dt.
=> u(t)=1/s.
=>t u(t)=1/s^2.
]

[
e^2t u(t)=1/(s-2).
=>-e^2t u(t)=-1/(s-2).
]

Then,

-e^2t u(t)*t u(t) = 1/s^2 *-1/s-2.

= -1/s^2(s-2).