How to compute a Fourier series: an example

Sdílet
Vložit
  • čas přidán 4. 06. 2009
  • Free ebook tinyurl.com/EngMathYT
    This video is a demonstration on how to compute a Fourier series of a simple given function. I discuss how to calculate the Fourier coefficients through integration and the simplifications involved.
    Fourier series are an important area of applied mathematics, engineering and physics that are used in solving partial differential equations, such as the heat equation and the wave equation. Fourier series are named after J. Fourier, a French mathematician who was the first to correctly model the diffusion of heat.
    Fourier series are seen in 2nd-year university mathematics.

Komentáře • 380

  • @MadeyeMoody492
    @MadeyeMoody492 Před 2 lety +49

    You know what they say. Better 2 hours before your final than never...

  • @DrChrisTisdell
    @DrChrisTisdell  Před 12 lety +29

    Wow - I'm really glad and humbled to receive a comment like yours. If you liked this video then there are lots more examples in my new (free) ebook, where each lesson is linked to a video of mine. The link is in the description. Good luck with Fourier series!

  • @965productions9
    @965productions9 Před 3 lety +52

    I have been trying to understand this for the past 12 hours and this video from 12 years ago is the biggest help I've found. Thank you so much sir!

  • @Murphyalex
    @Murphyalex Před 10 lety +94

    After such a frustrating day trying to organise all my printouts and really make a dent in my understanding of this, your video comes along at 1am and now I feel like I can sleep tonight. THANK YOU.

  • @RossJenk1
    @RossJenk1 Před 12 lety +28

    You are quite literally, single handedly saving my degree. My lecturers notes are shambolic compared to those which you produce, just a shame you're not my Engineering Mathematics II lecturer!

    • @frozenrats
      @frozenrats Před rokem +5

      How is life for you now 10 years later?

    • @RossJenk1
      @RossJenk1 Před rokem +5

      @frozenrat pretty good, thank you. Engineering wasn't really for me, I had a better head for business. So that's what I did, set up a medical engineering company and now hire 4 engineers.

    • @diags_1109
      @diags_1109 Před rokem +1

      @@RossJenk1 That's cool, also interesting looking at a video you watched 10 years ago haha

  • @arialamoosai3966
    @arialamoosai3966 Před 10 lety +28

    The best lecture i have seen on the Fourier Series ! Thank you .

  • @Ensign_Cthulhu
    @Ensign_Cthulhu Před 14 lety +3

    As always, you're crystal clear and your examples are easy to follow, even for someone who hasn't had formal university maths. I could quite happily watch these vids all day.

  • @mikey071113
    @mikey071113 Před 11 lety +1

    If only there were more professors like you online, I'd have a much greater understanding of all my subjects! Thanks!

  • @DrChrisTisdell
    @DrChrisTisdell  Před 12 lety

    Hi - here is a video on odd and even functions /watch?v=y69VgXFC1tU
    I have plenty of examples in my new and free ebook. The link is in the description.

  • @DrChrisTisdell
    @DrChrisTisdell  Před 12 lety +1

    No worries, mate! If you liked this video then I also recommend my new ebook. It's free and the link is in the description.

  • @davidfof13
    @davidfof13 Před 12 lety

    I really appreciate your work Dr Tisdell. Your explanations are very clear and you speak slowly allowing us, the viewers to easily adapt to the rhythm. many thanks. this vid has widened my vision of fourier series

  • @martafajlhauer8877
    @martafajlhauer8877 Před 7 lety +14

    I had 100% on my ODE mid-term thanks to you, now it's time for my final. I would love to repeat my score :) As my lecturer is not the best I can say that I had my score only thanks to Dr Chris. Thank you.

    • @martafajlhauer8877
      @martafajlhauer8877 Před rokem +1

      Ha! Thanks for the reminder. Do you know that I got 80%+ for my ODE in the end and I have studied for a week or so. I work as Data Scientist contractor at the space industry company. I think that these ODE went pretty well but will revise them one day. Highly recommended!

  • @troid
    @troid Před 13 lety +1

    Thank you for doing this! It means a lot for us students and learners. You've just covered two weeks of class in our school (which is sad). I just hope teachers would learn how to teach like you. Some of them feel they knew everything that they don't even want to learn new things (better way to teach).

  • @RossJenk1
    @RossJenk1 Před 11 lety +3

    Well my university have decided to screw me over because I had to get an operation and long story short I am now sitting this exam. Again. This video for a second time has helped me more than I could have imagined and the PDF is great! The one thing I'd suggest is possibly worked solutions but I appreciate how much time has already gone in to it out of your own goodness. Keep up the good work, much preferred channel over others such as Khan Academy. If I could hire for private tutoring I would!

  • @anannyauberoi7984
    @anannyauberoi7984 Před 6 lety +1

    Great explanation! Love the little simplification in the end- thanks a ton!

  • @2020LLL
    @2020LLL Před 11 lety

    finally someone who doesn't take for granted that everyone is born genius. Excellent tutorial and wonderful practice for us starters who have full-time everything going on yet wants to better themselves in understanding step by step and not skipping just because we should already know this... Please, more examples; and as you get more in depth, your followers will become more as well but with a greater concept than those who were born engineers.

  • @DrChrisTisdell
    @DrChrisTisdell  Před 12 lety +2

    Thanks for the feedback. Glad you are finding these things of some use. Next year I'll post a full course on PDE with a new, free ebook. Good luck with your studies.

  • @Tofumoode-jy6ro
    @Tofumoode-jy6ro Před 6 lety

    wow, you managed to explain what I've spent for over 6 hours trying to yet understand. Many thanks. :D

  • @ASFAnarchist
    @ASFAnarchist Před 11 lety

    Great! I remember learning this a few years back, but I urgently needed a refresher. This was exactly what I needed. Thank you!!

  • @DrChrisTisdell
    @DrChrisTisdell  Před 12 lety

    My pleasure. There are many more examples in my new ebook. The free download link is in the description.

  • @DrChrisTisdell
    @DrChrisTisdell  Před 12 lety

    Please check my other videos for non-square waves.

  • @DumboSanchez
    @DumboSanchez Před 10 lety +1

    Youre a legend Tisdell love your teaching style!

  • @Andiotic
    @Andiotic Před 12 lety

    Thank you very much sir, this is one of the most straight forward, easy to understand example I've seen so far.

  • @luthandondlovu8613
    @luthandondlovu8613 Před 5 lety +1

    DAMN DAMN DAMN WOW.......You have simplified the workload for me after trying many videos

  • @DrChrisTisdell
    @DrChrisTisdell  Před 12 lety

    Thanks! My new ebook is now available for free download. It contains more examples on Fourier series and each lesson is linked with a YT video. The link is on my YT Channel.

  • @DrChrisTisdell
    @DrChrisTisdell  Před 12 lety +15

    Look in my playlist "Fourier series"

    • @chekwubeugwu4015
      @chekwubeugwu4015 Před 2 lety +1

      Dr please what do I do to know this Fourier series. I have given it so much time but it seems not to sink in my memory

    • @colloupdated
      @colloupdated Před 2 lety

      @@chekwubeugwu4015 u have to believe in ur mind and ur ability to learn,as well as practice 💯 ...u will be gud

  • @sanchezdel8
    @sanchezdel8 Před 12 lety

    Wow! This is the explanation I've been looking for. VERY CLEAR. THANK YOU!!

  • @jackdavy9182
    @jackdavy9182 Před 6 lety

    This really helped me to understand when you can integrate from [0,L] instead of [-L,L]

  • @DrChrisTisdell
    @DrChrisTisdell  Před 12 lety +1

    Hi - thanks for the kind words. I have been at UNSW, Sydney for 10 years. During that time I, too, have learnt a lot from my colleagues. I've had a bit of experience with teacher training and get the trainee teachers to "critique" some of my videos, eg "What would you do differently?". You may also like to use YT as a learning tool in your own classroom at some stage. Good luck with teaching!

  • @DrChrisTisdell
    @DrChrisTisdell  Před 12 lety

    Glad you found it useful and hope you also take a look at my new ebook. The free link is in the description.

  • @ortek87
    @ortek87 Před 11 lety

    Sir, thank you for this. I think the true instructor should possess the characteristics that you have. Ours are always reluctant to give details about how to calculate, they even skip the intermediate parts in examples, they say it is our duty to find out how the calculations are carried out and our job to refresh our memories from calculus to carry out difficult integration by parts etc.
    4.5 hours to my final exam and thank you for making these available to us. You sir, are a great man!

  • @parveensharma75
    @parveensharma75 Před 6 lety

    Amazing explanation Chris Keep up your good work.

  • @MigLMariano
    @MigLMariano Před 13 lety +1

    Thank you so much, this was a great video to help refresh my memory for my final exam

  • @RandyLott
    @RandyLott Před 12 lety

    I haven't seen too many Australian people on these sort of videos. There's something about the accent that I love even though I'm American! Great work Chris.

  • @chevon1920
    @chevon1920 Před 13 lety

    I literally LOVE this man. This helped me soooo much!

  • @niftyusername
    @niftyusername Před 13 lety

    Very clear and awesome. Understanding is such a stress relief!

  • @BlakLotus
    @BlakLotus Před 11 lety

    I had no idea what my book was saying. You just saved my butt. Thanks a bundle!

  • @Arnab1actor
    @Arnab1actor Před 11 lety

    definately the easiest way on the internet to understand the concept of fourier series.. kudos!!!!!!

  • @ortek87
    @ortek87 Před 10 lety

    I got a total of 83 from differential equations course and got a BA. In the past, I would be walking on the clouds for such a grade, but now I feel for that missing AA :))) Thank you Dr. Tisdell, blessings to you

  • @DrChrisTisdell
    @DrChrisTisdell  Před 13 lety

    @marcjdesjardins Click on the link in the video to learn more about odd functions. See my comment below on doubling the integral.

  • @TheAnatomias2
    @TheAnatomias2 Před 13 lety

    Really nice explained Dr Chris,keep up the good work!Thanks

  • @ManuelMendez1
    @ManuelMendez1 Před 13 lety

    So many thanks from Dominican Republic, a VERY simple way to teach no simple things

  • @alreadytakenindeed
    @alreadytakenindeed Před 14 lety

    A guys like you, Chirs are giving the math a good name. You gave me hope :)

  • @mexico442
    @mexico442 Před 13 lety

    Wonderful job Dr. Tisdell. I should let you know that I've passed calculus because of your videos. Thanks!

  • @aluminous0
    @aluminous0 Před 12 lety +1

    Thank you so much! I was smashing my head against the wall for hours trying to figure this out before.

  • @danykelvin7720
    @danykelvin7720 Před 6 lety

    This is Really awesome! Just what i have been looking for... Thank you Sir!

  • @Beriszle
    @Beriszle Před 14 lety

    Hello, I am an aerospace engineering student getting ready to start my second year and I am just curious about this sort of thing. Just wanted to say very clear explanation and VERY interesting!

  • @DrChrisTisdell
    @DrChrisTisdell  Před 12 lety

    Hi - thanks. If you ennjoyed this video then I can't resist suggesting my new ebook, which is totally free and is designed to be used together with my videos. It is freely downloadable from the link on my YT Channel.

  • @Fatkaido
    @Fatkaido Před 5 měsíci

    Thank you Dr Tisdell. Im having an exam tomorrow and this is what's been keeping me awake until you appeared on my search results. I wish you the best as well🎉

  • @Saila36
    @Saila36 Před 4 lety

    This is exactly what I was looking for. THNX :)

  • @drdread
    @drdread Před 13 lety

    Thanks a lot for the brilliantly laid out and thorough example. Saved me a lot of headache!
    2nd Year Mechanical Engineering student at University of Nottingham

  • @WaqasKhan411
    @WaqasKhan411 Před 13 lety

    Thanks Dr. Chris for uploading such an informative video

  • @MsBourne47
    @MsBourne47 Před 9 lety +3

    awesome lesson man

  • @allinengineering8168
    @allinengineering8168 Před 2 lety

    I saw your video 5 years ago in my undergraduate degree now I am watching again in masters degree you are wonderful both lessons going well

  • @cemcalsar7367
    @cemcalsar7367 Před 2 lety

    thats what ı have been searching for, so you made it simple ,hocam thanx to you so much

  • @DrChrisTisdell
    @DrChrisTisdell  Před 15 lety +1

    That's it DMan - you got it!! Just in case you forget, if you follow my "is my integrand even or odd?" method (in the vid) then you can't go wrong!

  • @Lownayto
    @Lownayto Před 13 lety +1

    Thanks for uploading this, can't understand my actual professor. I love you forever good sir.

  • @nabilnader566
    @nabilnader566 Před 10 lety +2

    you are lifesaver dr chris .... could u do more video about Fourier series

  • @saadamiens
    @saadamiens Před 13 lety

    You are the best teacher on youtube

  • @dansdendanable
    @dansdendanable Před 4 lety

    Nice lecture! Well explained. Thanks

  • @ragnarlothbrok4090
    @ragnarlothbrok4090 Před 3 lety

    Sir you are best lectirer you deserve more recognition!

  • @kingrobin12
    @kingrobin12 Před 13 lety

    Man this is AWESOME!! You saved my exam!

  • @DrChrisTisdell
    @DrChrisTisdell  Před 12 lety

    My pleasure! My current mantra is: free videos + free ebooks = better education. I'm glad I could help.

  • @nablarnermk8844
    @nablarnermk8844 Před 7 měsíci

    Never lose trust in a 14 year old calculus video! Best video on this topic by far

  • @MDMAx
    @MDMAx Před 12 lety

    On behalf of all the undergraduate viewers I THANK YOU for your videos.
    Science bless technology advanced 21.st century.

  • @DxBoi
    @DxBoi Před 15 lety

    cheers mate. thanks for explaining it in that other way. helped out a lot.

  • @houssamzitouni2406
    @houssamzitouni2406 Před 6 lety

    Amazing Lecture !! Thank you !

  • @zayed9902
    @zayed9902 Před 2 měsíci

    Wow😮, you upload this video before i start kindergarten and now i watch it for my first year in engineering college

  • @DxBoi
    @DxBoi Před 15 lety

    thanks heaps Dr Chris! i see now what u were talking about...and thanks so much for all these awesome vids! i feel they're the best way to get started on a topic. cheers!

  • @brandonphan1437
    @brandonphan1437 Před 6 lety

    exactly what i was looking for.. thanks!

  • @sukd2669
    @sukd2669 Před 2 lety

    This is really helpful. Well done.

  • @JamesTuchel
    @JamesTuchel Před 14 lety

    Great stuff Dr. Chris! Thanks a ton.

  • @jeremymandela5400
    @jeremymandela5400 Před 5 lety

    THANKS A LOT Dr Chris Tisdell. Finally I get a full understanding on the whole thing. God bless you in your carrier.

  • @bearded-cat
    @bearded-cat Před 7 lety

    thanks a lot! I wish we had such lecturers in my uni

  • @06suyash
    @06suyash Před 10 lety

    sir u are the best i couldnt understand what is this bt after ur video i can finally clear my exam

  • @DrChrisTisdell
    @DrChrisTisdell  Před 13 lety +2

    @jackofnowhere Did you watch the video linked at 2:27? Maybe the best (and simplest) way to understand odd functions is to rotate the graph of the function 180 degrees about the origin and to see if you get the same graph as the original function.

  • @DrChrisTisdell
    @DrChrisTisdell  Před 15 lety

    Hi Steve
    D'Alembert's solution is used to solve PDEs with ONLY initial condtions. Separation of variables is used when there are both initial and boundary conditions. It's important to understand which method to use when.
    With D'Alembert's solution, you assume that the solution is of the form $u(x,t) = \phi(x + ct) + \psi(x - ct)$ and then you want to determine the functions $\phi$ and $\psi$ from the given initial conditions.
    Hope this helps!

  • @ew0054
    @ew0054 Před 13 lety +1

    Thank you so much for this video! You have taught me in 10 minutes what I have not been able to learn in class for the past month. I will be sure and pass this along to my friend who is equally struggling.
    I would like to ask, at 4:35, when you double the integral and 1/2 the length, what property allows this?

  • @DrChrisTisdell
    @DrChrisTisdell  Před 14 lety

    Always happy to help.

  • @DrChrisTisdell
    @DrChrisTisdell  Před 11 lety

    Glad to know they are useful to you. Thanks.

  • @theprodigalduck
    @theprodigalduck Před 8 lety

    Great video. Didn't know the even*odd functions integral trick, I just always had to integrate

  • @PokemonParadise2010
    @PokemonParadise2010 Před 13 lety

    Dr. Tisdell
    You have done a wonderful job with this video. This is excellent. I learn a lot from your videos. Please make more videos. You are great.
    Regards,
    SO

  • @khaaaled2007
    @khaaaled2007 Před 12 lety

    Thanks :) I'll watch all of them tonight , exams are just around the corner
    thanks again

  • @jaijeffcom
    @jaijeffcom Před 6 lety

    Fabulous. Enjoyed that a lot. Very clear.

  • @lifematch
    @lifematch Před 13 lety

    can you make more video of Fourier series. i really need to grasp this concept and your video was the clearest among other vids in terms of what to do with Fourier series. i would very much appreciated as will other students around the world. nonetheless thank you soo much for the lesson.

  • @Jonorocks999
    @Jonorocks999 Před 14 lety

    Top Video, really clear. Now Fourier is sorted for my exams...

  • @styno2010
    @styno2010 Před 10 lety +5

    Thanks a million.

  • @studiowomi7723
    @studiowomi7723 Před 2 lety

    we are greatful for provisions of your reference.from proff.Wanyoyi and Abbas from Kenya.

  • @sisip123
    @sisip123 Před 14 lety

    I'm currently cramming for MATH3121 .. this was good revision. thanks!

  • @DrChrisTisdell
    @DrChrisTisdell  Před 15 lety

    Hi Fartx: the $f(x)$ is usually a given function (given initial temperature). If $f$ is not specified then you can't do anything more than just write down the integral form for the $b_k$ as you have done above.
    Good luck!

  • @chuckjls
    @chuckjls Před 8 lety

    Nice video, Dr. Tisdell. I am looking for material that explains the derivation of the double Fourier series. Do you have any suggestions?

  • @fransiscocauchy309
    @fransiscocauchy309 Před 11 lety

    Very helpful video thanks alot for the Fourier transformation.

  • @TalhaKaka08
    @TalhaKaka08 Před 7 lety

    Massive help! Thank you!

  • @nikan4now
    @nikan4now Před 14 lety

    Thanks Chris. Very helpful.

  • @DrChrisTisdell
    @DrChrisTisdell  Před 12 lety

    Thanks! Hope you find the free ebook of some use also!

  • @banytoshbot
    @banytoshbot Před 13 lety

    Awesome explanation :D thanks alot Mr Tisdell!

  • @simrannahar8262
    @simrannahar8262 Před rokem

    this was super helpful sir thank you so much

  • @annmarryp.k.1283
    @annmarryp.k.1283 Před 5 lety

    Thank you, sir🙏it was really helpful

  • @mominator_
    @mominator_ Před rokem

    Thankyou man i really cant thank you enough this was so helpful

  • @confidencedavid8890
    @confidencedavid8890 Před 3 lety

    Most simplified..I've seen so far🙌