Finding Fourier Series Trouble












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There is a question in my homeworks and I couldn’t ask to professor since she has gone abroad. I don’t have any idea abot what should I do. I really need help. I have an exam this week. Any help will be very beneficial for me. Thanks a lot




Determine two periods for pointwise limit of Fourier Series of those functions below and determine Fourier Series are uniform convergent or not without calculating Fourier coefficients.




One of functions :



$$f(x)=e^x; -1lt x leq 1$$










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    2












    $begingroup$


    There is a question in my homeworks and I couldn’t ask to professor since she has gone abroad. I don’t have any idea abot what should I do. I really need help. I have an exam this week. Any help will be very beneficial for me. Thanks a lot




    Determine two periods for pointwise limit of Fourier Series of those functions below and determine Fourier Series are uniform convergent or not without calculating Fourier coefficients.




    One of functions :



    $$f(x)=e^x; -1lt x leq 1$$










    share|cite|improve this question









    $endgroup$















      2












      2








      2





      $begingroup$


      There is a question in my homeworks and I couldn’t ask to professor since she has gone abroad. I don’t have any idea abot what should I do. I really need help. I have an exam this week. Any help will be very beneficial for me. Thanks a lot




      Determine two periods for pointwise limit of Fourier Series of those functions below and determine Fourier Series are uniform convergent or not without calculating Fourier coefficients.




      One of functions :



      $$f(x)=e^x; -1lt x leq 1$$










      share|cite|improve this question









      $endgroup$




      There is a question in my homeworks and I couldn’t ask to professor since she has gone abroad. I don’t have any idea abot what should I do. I really need help. I have an exam this week. Any help will be very beneficial for me. Thanks a lot




      Determine two periods for pointwise limit of Fourier Series of those functions below and determine Fourier Series are uniform convergent or not without calculating Fourier coefficients.




      One of functions :



      $$f(x)=e^x; -1lt x leq 1$$







      functional-analysis analysis fourier-analysis fourier-series






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      asked Dec 25 '18 at 16:31









      user519955user519955

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          If you are expanding this function on $[-1,1]$, which means in terms of ${ e^{inpi x} }_{n=-infty}^{infty}$, then the Fourier series converges uniformly on every iterval $[a,b]subset(-1,1)$, but not on $[-1,1]$ because the periodic extension with period $2$ has a jump discontinuity at every integer. Uniform convergence would imply continuity.






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            $begingroup$

            If you are expanding this function on $[-1,1]$, which means in terms of ${ e^{inpi x} }_{n=-infty}^{infty}$, then the Fourier series converges uniformly on every iterval $[a,b]subset(-1,1)$, but not on $[-1,1]$ because the periodic extension with period $2$ has a jump discontinuity at every integer. Uniform convergence would imply continuity.






            share|cite|improve this answer









            $endgroup$


















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              $begingroup$

              If you are expanding this function on $[-1,1]$, which means in terms of ${ e^{inpi x} }_{n=-infty}^{infty}$, then the Fourier series converges uniformly on every iterval $[a,b]subset(-1,1)$, but not on $[-1,1]$ because the periodic extension with period $2$ has a jump discontinuity at every integer. Uniform convergence would imply continuity.






              share|cite|improve this answer









              $endgroup$
















                1












                1








                1





                $begingroup$

                If you are expanding this function on $[-1,1]$, which means in terms of ${ e^{inpi x} }_{n=-infty}^{infty}$, then the Fourier series converges uniformly on every iterval $[a,b]subset(-1,1)$, but not on $[-1,1]$ because the periodic extension with period $2$ has a jump discontinuity at every integer. Uniform convergence would imply continuity.






                share|cite|improve this answer









                $endgroup$



                If you are expanding this function on $[-1,1]$, which means in terms of ${ e^{inpi x} }_{n=-infty}^{infty}$, then the Fourier series converges uniformly on every iterval $[a,b]subset(-1,1)$, but not on $[-1,1]$ because the periodic extension with period $2$ has a jump discontinuity at every integer. Uniform convergence would imply continuity.







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                share|cite|improve this answer



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                answered Dec 26 '18 at 3:30









                DisintegratingByPartsDisintegratingByParts

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                59.3k42580






























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