Find the inverse laplace (if there is one)












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I need to find if F(s) can be a laplace transform of a continuous exponential function:



F(s)=s^3/(s^3+2s^2+s+1)



any ideas?






laplace-transform







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  • $begingroup$
    Well the fact that it doesn't vanish at infinity already means there's some kind of Dirac delta going on, are you prepared for that? If not then you've probably written the problem wrong. The fact that the roots of the cubic in the denominator are really nasty also suggests you may have written the problem wrong.
    $endgroup$
    – Ian
    Jan 13 at 1:48


















0












$begingroup$


I need to find if F(s) can be a laplace transform of a continuous exponential function:



F(s)=s^3/(s^3+2s^2+s+1)



any ideas?






laplace-transform







share|cite|improve this question











$endgroup$












  • $begingroup$
    Well the fact that it doesn't vanish at infinity already means there's some kind of Dirac delta going on, are you prepared for that? If not then you've probably written the problem wrong. The fact that the roots of the cubic in the denominator are really nasty also suggests you may have written the problem wrong.
    $endgroup$
    – Ian
    Jan 13 at 1:48
















0












0








0





$begingroup$


I need to find if F(s) can be a laplace transform of a continuous exponential function:



F(s)=s^3/(s^3+2s^2+s+1)



any ideas?






laplace-transform







share|cite|improve this question











$endgroup$




I need to find if F(s) can be a laplace transform of a continuous exponential function:



F(s)=s^3/(s^3+2s^2+s+1)



any ideas?






laplace-transform




laplace-transform






share|cite|improve this question















share|cite|improve this question













share|cite|improve this question




share|cite|improve this question








edited Jan 13 at 1:54







ece

















asked Jan 13 at 1:46









eceece

12




12












  • $begingroup$
    Well the fact that it doesn't vanish at infinity already means there's some kind of Dirac delta going on, are you prepared for that? If not then you've probably written the problem wrong. The fact that the roots of the cubic in the denominator are really nasty also suggests you may have written the problem wrong.
    $endgroup$
    – Ian
    Jan 13 at 1:48




















  • $begingroup$
    Well the fact that it doesn't vanish at infinity already means there's some kind of Dirac delta going on, are you prepared for that? If not then you've probably written the problem wrong. The fact that the roots of the cubic in the denominator are really nasty also suggests you may have written the problem wrong.
    $endgroup$
    – Ian
    Jan 13 at 1:48


















$begingroup$
Well the fact that it doesn't vanish at infinity already means there's some kind of Dirac delta going on, are you prepared for that? If not then you've probably written the problem wrong. The fact that the roots of the cubic in the denominator are really nasty also suggests you may have written the problem wrong.
$endgroup$
– Ian
Jan 13 at 1:48






$begingroup$
Well the fact that it doesn't vanish at infinity already means there's some kind of Dirac delta going on, are you prepared for that? If not then you've probably written the problem wrong. The fact that the roots of the cubic in the denominator are really nasty also suggests you may have written the problem wrong.
$endgroup$
– Ian
Jan 13 at 1:48












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$begingroup$

As Ian suggests, because of the equal polynomial orders in the numerator and the denominator, the inverse implicates the Dirac delta function. So the answer is no, F(s) is not a transform of a continuous exponential function.






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    0












    $begingroup$

    As Ian suggests, because of the equal polynomial orders in the numerator and the denominator, the inverse implicates the Dirac delta function. So the answer is no, F(s) is not a transform of a continuous exponential function.






    share|cite|improve this answer









    $endgroup$


















      0












      $begingroup$

      As Ian suggests, because of the equal polynomial orders in the numerator and the denominator, the inverse implicates the Dirac delta function. So the answer is no, F(s) is not a transform of a continuous exponential function.






      share|cite|improve this answer









      $endgroup$
















        0












        0








        0





        $begingroup$

        As Ian suggests, because of the equal polynomial orders in the numerator and the denominator, the inverse implicates the Dirac delta function. So the answer is no, F(s) is not a transform of a continuous exponential function.






        share|cite|improve this answer









        $endgroup$



        As Ian suggests, because of the equal polynomial orders in the numerator and the denominator, the inverse implicates the Dirac delta function. So the answer is no, F(s) is not a transform of a continuous exponential function.







        share|cite|improve this answer












        share|cite|improve this answer



        share|cite|improve this answer










        answered Jan 15 at 17:53









        SotirisSotiris

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