Proof: Euler's Formula for Plane Graphs | Graph Theory

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  • เผยแพร่เมื่อ 18 ธ.ค. 2024

ความคิดเห็น • 38

  • @WrathofMath
    @WrathofMath  3 หลายเดือนก่อน

    Support the production of this course by joining Wrath of Math as a Channel Member for exclusive and early videos, original music, and upcoming lecture notes for the graph theory series! Plus your comments will be highlighted for me so it is more likely I'll answer your questions!
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  • @555yashwant6
    @555yashwant6 ปีที่แล้ว +7

    Perfectly described in easy and simple language . All doubts cleared

  • @ulissemini5492
    @ulissemini5492 3 ปีที่แล้ว +9

    Great video! your enthusiasm makes a 15m proof feel like a 1 minute cat video

    • @WrathofMath
      @WrathofMath  3 ปีที่แล้ว +2

      Thanks so much! That is as high praise as I can hope for, thanks for watching and let me know if you ever have any questions!

  • @md8978
    @md8978 4 ปีที่แล้ว +6

    Your videos help me out so much!! I have exams soon and watching your videos make the work so much easier to understand. Thank you!!

    • @WrathofMath
      @WrathofMath  4 ปีที่แล้ว

      You're very welcome and thanks for watching! So glad the videos help, and good luck on your exams!

  • @mariaritacorreia9340
    @mariaritacorreia9340 11 หลายเดือนก่อน +3

    Thank you again.
    I didn't get the part on the minimum size condition. If it is minimum, how can we remove one edge?

  • @mike_the_tutor1166
    @mike_the_tutor1166 4 ปีที่แล้ว +3

    This is one of my favorite proofs and you've explained it beautifully! This is your best video yet! My only suggestion is to slow down your speech just a bit in future videos.

    • @WrathofMath
      @WrathofMath  4 ปีที่แล้ว +1

      It is a wonderful proof! Thanks a lot and I appreciate the feedback! I always try to monitor the speed of my voice, but sometimes I no doubt lose track of it. I've got to take more time to breathe - which will naturally slow me down a bit!

  • @cobrametaliks490
    @cobrametaliks490 ปีที่แล้ว +3

    Hi 👋🏻
    Could you make a video about Kuratowski theorem?
    Thank you for your work 🙏🏻

  • @blade2.056
    @blade2.056 8 วันที่ผ่านมา

    Beautifully explained better than my lecture notes which contains proof by induction( PS: We deep down all hate proof by induction xd )

  • @maxinimus
    @maxinimus ปีที่แล้ว +1

    awesome explanation and a very passionate one as well :)

  • @aispweelun
    @aispweelun 3 ปีที่แล้ว +2

    Hi, thanks for this video. I have a question
    For the contradiction proof, are we assuming that n - m + r ≠ 2 is true for graph G with a minimum edges e? If that's the case, I don't understand how the G-e graph contradicts the n - m + r ≠ 2 because m-1 edges is already less than the minimum edges e so n - m + r ≠ 2 shouldn't apply to it

    • @ulissemini5492
      @ulissemini5492 3 ปีที่แล้ว

      because after showing that n - m + r for G equals n - m + r for G-e it contradicts n - m + r ≠ 2
      basically, so long as there are cycles you can delete an edge from a cycle while leaving the formula unchanged, I like to think of applying this over and over until you get to a tree (no cycles) where we've already proven it!

    • @mrDustin0Channel
      @mrDustin0Channel 2 ปีที่แล้ว +1

      let the vars of G-e be n', m' and r'
      so G-e holds n'-m'+r'=2
      now place the vars of G inside it
      n'-m'+r'=2=n-(m-1)+(r-1)
      and get n'-m'+r'=2=n-m+r
      so we did not change anything by deleting the edge regarding the formular
      we know the formular holds for G-e
      thus the formular holds for G aswell

  • @benjaminlannis5050
    @benjaminlannis5050 7 หลายเดือนก่อน

    Can you prove the Jordan Curve Theorem?

  • @PunmasterSTP
    @PunmasterSTP 6 หลายเดือนก่อน

    Euler's Formula? More like "All these proofs are fantastic; thank ya'!" 👍

  • @jaeholee1092
    @jaeholee1092 3 ปีที่แล้ว

    Why do we remove an edge? When you use induction, aren't you supposed to go from k edges to k+1 edges?

  • @yeezyeez6326
    @yeezyeez6326 ปีที่แล้ว

    Hi why do we apply induction on m edges? Why not we apply induction on n vertices?

  • @abiralkalbani8751
    @abiralkalbani8751 2 ปีที่แล้ว

    Dr, Could you please prove this question?
    Let G and H be connected graphs different from K1 and K2.Show that both factors are paths or one is a path and the other a cycle.

  • @Kevin-xs1ft
    @Kevin-xs1ft 2 ปีที่แล้ว

    (Copied from J)
    Hi, thanks for this video. I have a question
    For the contradiction proof, are we assuming that n - m + r ≠ 2 is true for graph G with a minimum edge m? If that's the case, I don't understand how the G-e graph contradicts the n - m + r ≠ 2 because m-1 edges is already less than the minimum edges e so n - m + r ≠ 2 shouldn't apply to it

    • @rameezshafat
      @rameezshafat ปีที่แล้ว

      The task at hand involves proving a statement about a cycle graph. To do this, a minimum counterexample approach is being used, wherein the smallest possible instance that does not satisfy the statement is being considered. In order to prove the statement, it is necessary to show a contradiction, in this case we show it by deleting the edge. The goal of this contradiction is to demonstrate that the statement is, in fact, true for all cycle graphs, and that the counterexample is invalid.

  • @StrifeHale
    @StrifeHale 4 ปีที่แล้ว

    Perfect, thank you very much.

    • @WrathofMath
      @WrathofMath  4 ปีที่แล้ว +1

      My pleasure, thanks for watching!

  • @andreeduenas
    @andreeduenas 4 ปีที่แล้ว

    Thank you very much!

    • @WrathofMath
      @WrathofMath  4 ปีที่แล้ว +1

      My pleasure, thanks for watching!

  • @vishnum3690
    @vishnum3690 4 ปีที่แล้ว

    Amazing!

    • @WrathofMath
      @WrathofMath  4 ปีที่แล้ว

      Thanks for watching, Vishnu!

  • @sagnik.math7
    @sagnik.math7 3 ปีที่แล้ว

    great !!!

    • @WrathofMath
      @WrathofMath  3 ปีที่แล้ว +1

      Thank you! If you're looking for more graph theory check out my graph theory playlist! th-cam.com/play/PLztBpqftvzxXBhbYxoaZJmnZF6AUQr1mH.html

  • @gabrielpereiramendes3463
    @gabrielpereiramendes3463 4 ปีที่แล้ว

    #Excelent!

  • @bedrichmazourek3289
    @bedrichmazourek3289 3 ปีที่แล้ว

    I love you

  • @bowlineobama
    @bowlineobama ปีที่แล้ว

    I wish you would have used , V, E, and F labels instead of n, m and r.