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 2.2 Clear[inverseLaplace ] inverseLaplace [func_] :=(FullSimplify@* InverseLaplaceTransform )[func,  s,  t] Clear[functionList ] functionList = 3 s , 3 s + 2 , 3 (s + 2) 2 , 3 s 3 , 1 2 s 2 + 9 , 3 s 2 + 4 s + 8 , s + 4 s 2 + 4 s + 8 , 1 (s + 2) 2 ; ({#, inverseLaplace /@ #} & [functionList ])// Transpose // Grid[#, Frame All] & 3 s 3 3 2+s 3 -2 t 3 (2+s) 2  3 ⅇ -2 t t 3 s 3 3 t 2 2 1 2 9+s 2 1 6 Sin[3 t] 3 8+4 s+s 2  3 ⅇ -2 t Cos[t] Sin[t] 4+s 8+4 s+s 2  -2 t (Cos[2 t]+ Sin[2 t]) 1 (2+s) 2  -2 t t 2.3 Solve[LaplaceTransform [x ′′ [t]+ 4 x [t]+ 3 x[t] UnitStep[t], t , s ]/. {x[0] 0, x [0] 0, LaplaceTransform [x[t], t , s] x}, x ] x  1 s 3 + 4 s + s 2 Solve[LaplaceTransform [x ′′ [t]+ 2 x [t]+  x[t] UnitStep[t], t , s ]/. {x[0] 1, x [0] 1, LaplaceTransform [x[t], t , s] x}, x ] x  1 + 3 s + s 2 s (1 + s) 2 Solve[LaplaceTransform [x ′′ [t]+ 2 x [t]+  x[t] UnitStep[t], t , s ]/. {x[0] 0, x [0] 0, LaplaceTransform [x[t], t , s] x}, x ] x  1 s (1 + s) 2

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  • 2.2

    Clear[inverseLaplace]inverseLaplace[func_] := (FullSimplify@*InverseLaplaceTransform)[func, s, t]

    Clear[functionList]

    functionList = 3

    s,

    3

    s + 2,

    3

    (s + 2)2,

    3

    s3,

    1

    2 s2 + 9,

    3

    s2 + 4 s + 8,

    s + 4

    s2 + 4 s + 8,

    1

    (s + 2)2;

    ({#, inverseLaplace /@ #} &[functionList]) // Transpose // Grid[#, Frame All] &

    3s

    33

    2+s3 -2 t

    3(2+s)2

    3 -2 t t

    3

    s33 t2

    21

    2 9+s2

    16Sin[3 t]

    3

    8+4 s+s23 -2 t Cos[t] Sin[t]

    4+s

    8+4 s+s2-2 t (Cos[2 t] + Sin[2 t])

    1

    (2+s)2-2 t t

    2.3

    Solve[LaplaceTransform[x[t] + 4 x[t] + 3 x[t] UnitStep[t], t, s] /.{x[0] 0, x[0] 0, LaplaceTransform[x[t], t, s] x}, x]

    x 1

    s 3 + 4 s + s2

    Solve[LaplaceTransform[x[t] + 2 x[t] + x[t] UnitStep[t], t, s] /.{x[0] 1, x[0] 1, LaplaceTransform[x[t], t, s] x}, x]

    x 1 + 3 s + s2

    s (1 + s)2

    Solve[LaplaceTransform[x[t] + 2 x[t] + x[t] UnitStep[t], t, s] /.{x[0] 0, x[0] 0, LaplaceTransform[x[t], t, s] x}, x]

    x 1

    s (1 + s)2