Shift Theorem Or the First Transform theorem:
Statement: If F(s) is the Laplace Transform of f(t), then F(s-a) is the Laplace transform of exp(at).f(t) .
Proof:
(integral limit is from 0 to infinity)
L{ e^(at) . f(t) } = integ { e^ (-st) e^ (at) f(t) dt } = integ { e^( - (s-a)t ) f(t) dt }
put s-a=s', so that
L { e^ (at) . f(t) } = integ { e^ (-s' t) f(t) dt } = F(s' ) = F(s-a)
this completes the proof.
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Laplace Transform is a Linear Operator:( Linearity Property Of Laplace Transform)
L { a f(t) + b g(t) } = a L { f(t) } + b L { g(t) }
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