The LaPlace transform of the given DE is

s² F(s) - s f(0) – f’(0) – 4[sF(s)- f(0)] +3F(s)= 8[1/s+1]

( s² – 4s +3)F(s)= sf(0)+ f ’(0) -4f(0) +8/(s+1), where y is f(t) and Lapalce transform of f(t) is denoted by F(s).

The inverse transform of F(s) can be carried out only if the initial conditions namely f(0 and f ‘ (0) are specified. Since these are not given, inverse transform of F(s) cannot be determined.

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