Oxford Calculus: Separable Solutions to PDEs

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  • Опубліковано 30 лип 2022
  • University of Oxford mathematician Dr Tom Crawford explains how to solve PDEs using the method of "separable solutions". Links to worksheets and app download below.
    Test yourself with some exercises on separable solutions with this FREE worksheet in Maple Learn: learn.maplesoft.com/doc/i72ve...
    Investigate separable solutions to the Heat Equation with this FREE worksheet in Maple Learn: learn.maplesoft.com/d/PQOSOUL...
    Check your working using the Maple Calculator App - available for free on Google Play and the App Store.
    Android: play.google.com/store/apps/de...
    Apple: apps.apple.com/us/app/maple-c...
    The technique of solving PDEs using separable solutions is introduced and then used to solve two examples. In both cases the technique of "separation of variables" is required.
    Other videos in the Oxford Calculus series can be found here: • Oxford Calculus
    Finding critical points for functions of several variables: • Oxford Calculus: Findi...
    Classifying critical points using the method of the discriminant: • Oxford Calculus: Class...
    Partial differentiation explained: • Oxford Calculus: Parti...
    Second order linear differential equations: • Oxford Mathematics Ope...
    Integrating factors explained: • Oxford Calculus: Integ...
    Solving simple PDEs: • Oxford Calculus: Solvi...
    Jacobians explained: • Oxford Calculus: Jacob...
    Separation of variables integration technique explained: • Oxford Calculus: Separ...
    Solving homogeneous first order differential equations: • Oxford Calculus: Solvi...
    Taylor’s Theorem explained with examples and derivation: • Oxford Calculus: Taylo...
    Heat Equation derivation: • Oxford Calculus: Heat ...
    Find out more about the Maple Calculator App and Maple Learn on the Maplesoft UA-cam channel: / @maplesoft
    Produced by Dr Tom Crawford at the University of Oxford. Tom is an Early-Career Teaching and Outreach Fellow at St Edmund Hall: www.seh.ox.ac.uk/people/tom-c...
    For more maths content check out Tom's website tomrocksmaths.com/
    You can also follow Tom on Facebook, Twitter and Instagram @tomrocksmaths.
    / tomrocksmaths
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    / tomrocksmaths
    Get your Tom Rocks Maths merchandise here:
    beautifulequations.net/collec...

КОМЕНТАРІ • 33

  • @TomRocksMaths
    @TomRocksMaths  Рік тому +3

    Test yourself with some exercises on separable solutions with this FREE worksheet in Maple Learn: learn.maplesoft.com/d/COKQBLEMDIGTPODOJIPGMQHKIPBGAMIQOOIGJSKTDFIOELMPEPERDKJHLRIIEHGHMHKQGLLTNLCLOFGTOGONMMDJINDTGSALDFPR

  • @Spectator007
    @Spectator007 Рік тому +10

    If I took my Fourier analysis class a quarter earlier this video wouldn't have been posted. Now I get MGK as my math tutor. You make me really enjoy my uni class even though you are sadly not my professor.

  • @weonlygoupfromhere7369
    @weonlygoupfromhere7369 Рік тому +15

    I love how you teach complex topics simpler than a good chunk of professors. They just explain it but don't give you an in-depth and step by step explanation

  • @wez7279
    @wez7279 Рік тому +7

    Was literally going to recap this topic today after finishing my first year, perfect timing!

  • @sunandinighosh6037
    @sunandinighosh6037 Рік тому +4

    Yesterday I was trying to understand the solution of Schrodinger's equation for my physics exam and couldn't understand the method...thankfully today you uploaded this video. What a coincidence!!

  • @bos567564
    @bos567564 Рік тому +9

    Hi Tom. I'm from South Africa. I just wanted to thank you for your channel. I wasn't very good at maths at school. In fact, I really struggled with it, especially with geometry .Since leaving school, I have started learning maths again. It has become a sort of hobby of mine. Maths is in my opinion the most interesting subject I have ever learnt after philosophy (that will always be my first joy, because I believe it is even more fundamental than maths, although you might disagree with me haha) 😀. Your channel gives me hope that I can learn and will improve. So thanks a lot, and keep making videos for us your maths fans!

  • @jcleary3134
    @jcleary3134 2 місяці тому

    I was reading the textbook for an hour+, and this video just saved me. Thank you sir.

  • @cristianorlandoelpro416
    @cristianorlandoelpro416 Рік тому +1

    Mate, my textbook did a horrible job explaining this topic. I'm glad I came across your vid

  • @giosanchez2714
    @giosanchez2714 Рік тому +2

    Excited for this one!

  • @peterhall6656
    @peterhall6656 Рік тому +4

    Separability ultimately has its physical justification in the assumed independence of the functional relations. This is quite believable in all the major PDEs which arose form looking at physical phenomena. Just look at how Maxwell derived his velocity distribution law to appreciate the independence angle.

  • @HuyNguyen-wj1ho
    @HuyNguyen-wj1ho Рік тому +1

    What a great and clear lecture. Thank you very much Dr. Tom. Waiting for your next lecture.😊

  • @nicholasifeajika1827
    @nicholasifeajika1827 Рік тому +1

    Great explanation. Easy to understand

  • @BlackEyedGhost0
    @BlackEyedGhost0 Рік тому +1

    Had to go back and review linear differential equations before I could remember how to do this. Thanks for the practice problems. Apparently I needed the practice.

  • @aniketeuler6443
    @aniketeuler6443 Рік тому +1

    Pretty excited sir!

  • @Au-fx4pv
    @Au-fx4pv Рік тому

    Thanks for helping me!!!

  • @M.athematech
    @M.athematech Рік тому +10

    Hi Tom, like John I am also from South Africa, but I was very good at maths at school and went on to complete my PhD at 24. I wasn't very good at begging people to give me money to do maths research though and started an IT company instead. But anyway, D = 1 doesn't follow from u(1,1) = e. The most one can say is that D and C are related by D = e^(1-3C/2).

    • @TomRocksMaths
      @TomRocksMaths  Рік тому +5

      I suppose I’m really appealing to uniqueness of the solution (my bad for failing to state this explicitly).

  • @priscillaflores3082
    @priscillaflores3082 Рік тому

    Great explanation

  • @arjunsinha4015
    @arjunsinha4015 Рік тому +1

    Nice video sir

  • @user-mb6gv6ez3e
    @user-mb6gv6ez3e 7 місяців тому

    Thank you sir

  • @two697
    @two697 Рік тому

    How do you know the only solution is in this form though? How do you know it isn't a linear combination of them? For example f(x)+g(y)

    • @TomRocksMaths
      @TomRocksMaths  Рік тому

      We rely on being able to show the PDE has a unique solution, which can be done for most of the examples seen here.

    • @MrFtriana
      @MrFtriana Рік тому

      You must check that this solution satisfies the boundary conditions. If two different solutions of a given PDE satisfies the same boundary conditions, it can be assumed that they are the same.

    • @travischism
      @travischism Рік тому

      if we label f(x) == ln(F(x)) and g(x) == ln(G(x)) then
      u(x,y) == f(x) + g(x) == ln(f(x)) +ln(G(x)) == ln(F(x)•G(x)) and now the solution U(x,y) == exp(u(x,y)) == F(x)•G(x)

  • @ronanmccluskey900
    @ronanmccluskey900 Рік тому +2

    Why does D=1 when u(1,1)=e??

    • @TomRocksMaths
      @TomRocksMaths  Рік тому +2

      I’m appealing to the unique solution property (without proving it - my bad).

    • @felipesernabarbosa2796
      @felipesernabarbosa2796 6 місяців тому

      D = exp(1 - 3c/2), I believe.@@TomRocksMaths

  • @jakobandrews2096
    @jakobandrews2096 Місяць тому

    When you say u(1,1) = e, wouldn't D=1/e and C=4/3 also work? I feel there is an infinite number of constants that work here

  • @camachojankowilderbeismar6167
    @camachojankowilderbeismar6167 Рік тому +2

    Hello

  • @MisterTutor2010
    @MisterTutor2010 6 місяців тому

    Logan Paul does PDEs? :)

  • @raneena5079
    @raneena5079 Рік тому

    I feel really weird just assuming that it's separable with no justification :/

    • @TomRocksMaths
      @TomRocksMaths  Рік тому +2

      It’s a standard technique to try and if it happens to work, then we can appeal to the uniqueness of solutions to claim it is the only solution (and in some sense we made a lucky/good first guess).