Inverse Fourier transform of $frac{jwL}{R+jwl}$











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I am trying to find the inverse Fourier transform of:



$$frac{jwL}{R+jwl}$$



My current attempt is



$$mathcal{F^{-1}(frac{jwL}{R+jwl})}$$
$$mathcal{F^{-1} ({jwL})} oplus mathcal{F^{-1}(frac{1}{R+jwL}}) $$
$$L.mathcal{F^{-1} ({jw}}) oplus frac{1}{L}.mathcal{F^{-1}(frac{1}{frac{R}{L}+jw}}) $$
$$ L.mathcal{F^{-1} ({jw}}) oplus frac{1}{L}.u(t).e^{frac{Rt}{L}} $$



I get stuck with $$ mathcal{F^{-1} ({jw}}) $$ as $$frac{1}{2 pi} int_{-infty}^infty jwe^{jwt} $$ doesn't converge










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    up vote
    1
    down vote

    favorite












    I am trying to find the inverse Fourier transform of:



    $$frac{jwL}{R+jwl}$$



    My current attempt is



    $$mathcal{F^{-1}(frac{jwL}{R+jwl})}$$
    $$mathcal{F^{-1} ({jwL})} oplus mathcal{F^{-1}(frac{1}{R+jwL}}) $$
    $$L.mathcal{F^{-1} ({jw}}) oplus frac{1}{L}.mathcal{F^{-1}(frac{1}{frac{R}{L}+jw}}) $$
    $$ L.mathcal{F^{-1} ({jw}}) oplus frac{1}{L}.u(t).e^{frac{Rt}{L}} $$



    I get stuck with $$ mathcal{F^{-1} ({jw}}) $$ as $$frac{1}{2 pi} int_{-infty}^infty jwe^{jwt} $$ doesn't converge










    share|cite|improve this question


























      up vote
      1
      down vote

      favorite









      up vote
      1
      down vote

      favorite











      I am trying to find the inverse Fourier transform of:



      $$frac{jwL}{R+jwl}$$



      My current attempt is



      $$mathcal{F^{-1}(frac{jwL}{R+jwl})}$$
      $$mathcal{F^{-1} ({jwL})} oplus mathcal{F^{-1}(frac{1}{R+jwL}}) $$
      $$L.mathcal{F^{-1} ({jw}}) oplus frac{1}{L}.mathcal{F^{-1}(frac{1}{frac{R}{L}+jw}}) $$
      $$ L.mathcal{F^{-1} ({jw}}) oplus frac{1}{L}.u(t).e^{frac{Rt}{L}} $$



      I get stuck with $$ mathcal{F^{-1} ({jw}}) $$ as $$frac{1}{2 pi} int_{-infty}^infty jwe^{jwt} $$ doesn't converge










      share|cite|improve this question















      I am trying to find the inverse Fourier transform of:



      $$frac{jwL}{R+jwl}$$



      My current attempt is



      $$mathcal{F^{-1}(frac{jwL}{R+jwl})}$$
      $$mathcal{F^{-1} ({jwL})} oplus mathcal{F^{-1}(frac{1}{R+jwL}}) $$
      $$L.mathcal{F^{-1} ({jw}}) oplus frac{1}{L}.mathcal{F^{-1}(frac{1}{frac{R}{L}+jw}}) $$
      $$ L.mathcal{F^{-1} ({jw}}) oplus frac{1}{L}.u(t).e^{frac{Rt}{L}} $$



      I get stuck with $$ mathcal{F^{-1} ({jw}}) $$ as $$frac{1}{2 pi} int_{-infty}^infty jwe^{jwt} $$ doesn't converge







      fourier-transform






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      edited Nov 20 at 21:38

























      asked Nov 20 at 20:18









      C. Begley

      105




      105






















          1 Answer
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          accepted










          Recall that:




          1. $$mathcal{F}(e^{-alpha t}u(t)) = frac{1}{alpha + jomega};$$

          2. $$mathcal{F}(delta(t)) = 1.$$


          Notice that:
          $$frac{jomega L}{R+jomega L} = frac{jomega L + R - R}{R+jomega L} = 1- frac{R}{R+jomega L}.$$



          The inverse Fourier transform of is:



          $$delta(t) - frac{R}{L}e^{-frac{Rt}{L}}u(t).$$






          share|cite|improve this answer























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            1 Answer
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            active

            oldest

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            1 Answer
            1






            active

            oldest

            votes









            active

            oldest

            votes






            active

            oldest

            votes








            up vote
            1
            down vote



            accepted










            Recall that:




            1. $$mathcal{F}(e^{-alpha t}u(t)) = frac{1}{alpha + jomega};$$

            2. $$mathcal{F}(delta(t)) = 1.$$


            Notice that:
            $$frac{jomega L}{R+jomega L} = frac{jomega L + R - R}{R+jomega L} = 1- frac{R}{R+jomega L}.$$



            The inverse Fourier transform of is:



            $$delta(t) - frac{R}{L}e^{-frac{Rt}{L}}u(t).$$






            share|cite|improve this answer



























              up vote
              1
              down vote



              accepted










              Recall that:




              1. $$mathcal{F}(e^{-alpha t}u(t)) = frac{1}{alpha + jomega};$$

              2. $$mathcal{F}(delta(t)) = 1.$$


              Notice that:
              $$frac{jomega L}{R+jomega L} = frac{jomega L + R - R}{R+jomega L} = 1- frac{R}{R+jomega L}.$$



              The inverse Fourier transform of is:



              $$delta(t) - frac{R}{L}e^{-frac{Rt}{L}}u(t).$$






              share|cite|improve this answer

























                up vote
                1
                down vote



                accepted







                up vote
                1
                down vote



                accepted






                Recall that:




                1. $$mathcal{F}(e^{-alpha t}u(t)) = frac{1}{alpha + jomega};$$

                2. $$mathcal{F}(delta(t)) = 1.$$


                Notice that:
                $$frac{jomega L}{R+jomega L} = frac{jomega L + R - R}{R+jomega L} = 1- frac{R}{R+jomega L}.$$



                The inverse Fourier transform of is:



                $$delta(t) - frac{R}{L}e^{-frac{Rt}{L}}u(t).$$






                share|cite|improve this answer














                Recall that:




                1. $$mathcal{F}(e^{-alpha t}u(t)) = frac{1}{alpha + jomega};$$

                2. $$mathcal{F}(delta(t)) = 1.$$


                Notice that:
                $$frac{jomega L}{R+jomega L} = frac{jomega L + R - R}{R+jomega L} = 1- frac{R}{R+jomega L}.$$



                The inverse Fourier transform of is:



                $$delta(t) - frac{R}{L}e^{-frac{Rt}{L}}u(t).$$







                share|cite|improve this answer














                share|cite|improve this answer



                share|cite|improve this answer








                edited Nov 20 at 20:39

























                answered Nov 20 at 20:26









                the_candyman

                8,55921944




                8,55921944






























                     

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