Introduction to eigenvalues and eigenvectors | Linear Algebra | Khan Academy

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  • เผยแพร่เมื่อ 26 ม.ค. 2025

ความคิดเห็น • 91

  • @joerich9636
    @joerich9636 9 ปีที่แล้ว +166

    How I wish Khan Academy existed when I was a student in the late 60s early 70s.

    • @razoredge8284
      @razoredge8284 4 ปีที่แล้ว +8

      shut up boomer

    • @AS-nx9fu
      @AS-nx9fu 4 ปีที่แล้ว +5

      @@razoredge8284 😂😂😂😭😭😭

    • @josuequintero-td5gh
      @josuequintero-td5gh 8 หลายเดือนก่อน +3

      I can't imagine school without the internet

  • @francoisbe92
    @francoisbe92 12 ปีที่แล้ว +38

    The eigenvectors of a transformation are the non-zero vectors that remain parallel to the original vector after the transformation.
    The eigenvalue is the scalar that gives you the vector (if you have a transformation A, a vector v and a scalar t --> Av=tv. t is the eigenvalue).

  • @guilbas1
    @guilbas1 12 ปีที่แล้ว

    I'm from brazil and I have a Russian linear algebra teacher who barely speaks portuguese, THANK GOD for Khanacademy!

  • @dauntSilver
    @dauntSilver 13 ปีที่แล้ว +8

    "if this doesnt look familiar to you, i can jog your memory a little bit"... he read my freakin mind! love this guy.

  • @utsawin09
    @utsawin09 12 ปีที่แล้ว +50

    has this guy been on the front cover of time magazine??
    he fuckin should be.

  • @akj375
    @akj375 13 ปีที่แล้ว +9

    If I may be so bold as to suggest... could you please number the videos in each category or subject heading? That way if one doesn't catch some of the concepts in the current video, he can always go back successively until he gets to a point where he's comfortable and can again start moving forward. Much much appreciated. Thank you for everything that you do!

  • @moonman239
    @moonman239 7 ปีที่แล้ว +19

    So, an eigenvector is simply the vector that's scaled by the multiple that is also known as the eigenvalue.

  • @monroe444444
    @monroe444444 11 ปีที่แล้ว +62

    These videos would be so much more useful if we could tell which videos preceded them, as you say to do in the video itself. I have just been searching on Khan Academy for this video and the ones you way to watch before it, but I can't even find this one.

    • @jnv1971
      @jnv1971 10 ปีที่แล้ว +15

      You must be searching manually on khanacademy then, which is a pretty terrible idea.
      If I were you, I'd just log in to khanacademy and write the name of this video into the big searchbox at the top of the page.

  • @MarineFocus
    @MarineFocus 12 ปีที่แล้ว +1

    My prof said something about that, and no it does not make a difference except for negative signs. But since you're going to compute det(A - lambda * i) = 0 a lot of the time, the negative signs won't matter because the right hand side is 0 anyways

  • @TheYipedo
    @TheYipedo 11 ปีที่แล้ว

    There's a reason why he's requesting it while still being grateful and not demanding it like he's entitled to it. The purpose of this video is to help other people learn linear algebra. It's just a mere suggestion that will help people cruise through the vids swimmingly without potentially skipping crucial lessons along the way.

  • @MisterLiBRiUMz
    @MisterLiBRiUMz 11 ปีที่แล้ว +1

    I really appreciate the videos. I've got my Linear Algebra exam Monday for my first year Engineering, (Will be specifying in Chemical Engineering 2nd Year) and I can stress by saying thanks for uploading these awesome videos.

    • @monamahmod8976
      @monamahmod8976 7 ปีที่แล้ว

      I guess you are a graduate now if so good luck

  • @shonhayashi
    @shonhayashi 13 ปีที่แล้ว +3

    Wow, thank you so much for putting up these videos! You teach it much better than my lin alg prof, who never once explained the geometric meaning of eigenvectors/values

  • @MightyGoldenBoy
    @MightyGoldenBoy 15 ปีที่แล้ว +1

    Thank you!!!! just started my several variable calculus and the lecturer explained this in under five secounds :P Now i get it!

  • @TheFarrukhnaveed
    @TheFarrukhnaveed 12 ปีที่แล้ว

    Please Plz Plz :Provide index of ur lectures...plz.... they are so good.

  • @SergiuMunteanu
    @SergiuMunteanu 11 ปีที่แล้ว +2

    You are the best math teacher I know. Keep up the good work.

  • @TheAncientScholar
    @TheAncientScholar 13 ปีที่แล้ว

    @imamnalog: One important, practical meaning is that Eigenvalues in the time independent form of the wave equation represent the binding energies of an electron in a Hydrogen atom at a given value called "n." This is in fact where we get the quantum numbers values for "n." They basically fall out of the Eigenvalue solutions.

  • @SpiritVector
    @SpiritVector 4 ปีที่แล้ว

    Thanks to this guy, I am fluent in Group theory, and Number theory.

  • @vishalvisd4
    @vishalvisd4 14 ปีที่แล้ว

    Dear sir, you are really a big help...thanx...

  • @譚文雪
    @譚文雪 9 หลายเดือนก่อน

    I ❤ u,u r my real professor,my tuition fee should give u ,really!

  • @abhishekravindra4008
    @abhishekravindra4008 6 ปีที่แล้ว

    Best expalanation of eigenvalues and eigenvectors upto date

  • @vivekkumar-py6kp
    @vivekkumar-py6kp 5 ปีที่แล้ว +1

    Which previous video are you talking about??please help me

  • @macerik628
    @macerik628 10 ปีที่แล้ว

    Right pace, clear, no waffle. Thanks
    ot: what s/ware are you using - looks very effective

  • @Phagocytosis
    @Phagocytosis 11 ปีที่แล้ว +4

    While that would be useful, you might consider watching the videos on the Khan Academy website instead -- it even has a cool scoring system that just makes it more fun and motivating if you're the right type of person for that kind of thing -- where they are all listed in categories and sub-categories and in order.

  • @arsenalwak
    @arsenalwak 12 ปีที่แล้ว +3

    So what is the definition of an eigenvector and eigenvalue, something i could write in an exam please.

  • @ivancarrillo1889
    @ivancarrillo1889 4 ปีที่แล้ว +2

    I felt quite intimated by these vectors name not able to grasp what they were. Thanks for such a quiet simple yet powerful explanation.

    • @jacobsan
      @jacobsan 11 หลายเดือนก่อน

      It's actually quite simpler than it sounds lol

  • @shotcallerpat
    @shotcallerpat 14 ปีที่แล้ว

    @Lexorinox Yeah it's pretty bad huh? Are you going to Berkeley? This helps so much.

  • @jkjonk
    @jkjonk 12 ปีที่แล้ว

    I swear I just go to class now just to talk. Thanks Khan!!!

  • @taviona
    @taviona 14 ปีที่แล้ว +2

    Wow, that was so helpful.

  • @nochiill376
    @nochiill376 7 ปีที่แล้ว +7

    Can you please make a video on Diagonalisation Theorem?

    • @yousuffarhan963
      @yousuffarhan963 5 ปีที่แล้ว

      Cantor's Diagnalization Theorem?

  • @Seakros
    @Seakros 15 ปีที่แล้ว +1

    Once again,many thanks for your videos you are doing a great job!

  • @tymothylim6550
    @tymothylim6550 3 ปีที่แล้ว +1

    Thank you very much for this video! It really helped to explain eigenvectors of transformations as those that are simply scaled by a scalar (i.e. the associated eigenvalue)! The rotation analogy of the 2D case really helps visualize it!

  • @barzhikevil6873
    @barzhikevil6873 6 ปีที่แล้ว

    Thanks for sharing!

  • @nm4k4
    @nm4k4 12 ปีที่แล้ว +1

    Thank you for this intuitive explanation!

  • @omarolocabe
    @omarolocabe 15 ปีที่แล้ว

    Awesome....thanks..it was helpful...

  • @galotalp
    @galotalp 14 ปีที่แล้ว

    please please please do a video on principle component analysis

  • @mrfrankincense
    @mrfrankincense 10 ปีที่แล้ว +1

    Hey, Sal, I couldn't find a lot of the linear algebra videos directly from the playlist. Have I made a mistake, or have some not been put in the playlist?

  • @lamtartarus
    @lamtartarus 13 ปีที่แล้ว

    does it make a difference if its (A - lambda*i) instead of (lambda*i - A)?

  • @blackphosphor
    @blackphosphor 13 ปีที่แล้ว

    Khan your everywhere! awesome!

  • @ash11music
    @ash11music 5 ปีที่แล้ว

    Can anyone plz send the link to the video where he explains about the reflection about the line? Thanks!

  • @aishah8398
    @aishah8398 3 ปีที่แล้ว +1

    thank you khan academy... I wonder how one can make this horrible stuff so simple n understandable...you are one of the best math n stats teachers

  • @mrannabee33
    @mrannabee33 13 ปีที่แล้ว

    Can you put sound on these? it's hard to read and pay attention to what you're doing at the same time

  • @CyberneticOrganism01
    @CyberneticOrganism01 14 ปีที่แล้ว +1

    Thanks, very helpful!

  • @hongsukchun
    @hongsukchun 11 ปีที่แล้ว

    Finding it is your job. It's already a free video, I don't think the purpose of this video is to serve other's rights, just a helping tutorial.

  • @ShermanSitter
    @ShermanSitter 5 ปีที่แล้ว

    its good to watch the whole thing, but the answer is at 4:45

  • @BlazeMrdr
    @BlazeMrdr 12 ปีที่แล้ว

    if you go to his site everything is ordered by subjects and is in chronological order.

  • @imamnalog
    @imamnalog 13 ปีที่แล้ว

    Ok . . . and what's the practical meaning of these eigenvalues in Schrodinger's equation ? ? ?

  • @wickedm348
    @wickedm348 10 ปีที่แล้ว +1

    Sal, you got me man. Really appreciate your work.

  • @dheerajsinghal8802
    @dheerajsinghal8802 10 ปีที่แล้ว +2

    hey salman sir thank you very much for providing us such a great platform. That was the best explanation i ever heard thank u you very much.

  • @medetkhanaltynbek1442
    @medetkhanaltynbek1442 6 ปีที่แล้ว

    Could you please create video about Lie derivatives, Lyapunov function..all about nonlinear dynamical systems?

  • @vb4max
    @vb4max 14 ปีที่แล้ว

    thank you

  • @imbsalstha
    @imbsalstha 12 ปีที่แล้ว

    many many thanks again

  • @Zoku012
    @Zoku012 11 ปีที่แล้ว

    Does an eigenvalue correspond to the slope of the spanning line? For example, the line he drew corresponding to lambda = 5 has a slope of 5 right?

  • @x.m.caucase7841
    @x.m.caucase7841 10 ปีที่แล้ว +2

    Just something I don't get. How do you deduce T(v)=lamnda*v - Av from T(x)=Ax ?
    Is there a difference between x and v? If not does it mean
    lamnda*v - Av = Av ?
    Is my question stupid?

    • @x.m.caucase7841
      @x.m.caucase7841 10 ปีที่แล้ว +3

      Actually, the next video answered my question! xD

    • @cristic767
      @cristic767 9 ปีที่แล้ว

      X.M. Caucase , how did you identified "next video"? They're not numbered?
      I would like to get a list, but I don't figure it out. :(
      Can you help me, please?
      Thank you.

    • @x.m.caucase7841
      @x.m.caucase7841 9 ปีที่แล้ว +1

      Oh, it's been a while now. I think the video I was talking about is "finding eigenvalues and eigenvectors examples". I don't remember if identified a "next video".

    • @sillystranger3721
      @sillystranger3721 6 ปีที่แล้ว

      @@x.m.caucase7841 lolz

  • @StarXnauti
    @StarXnauti 5 ปีที่แล้ว

    Didnt he draw the flipped version of V1 wrong? Or do i just understand it badly? Because its not in its span.

  • @frozenstrawbs
    @frozenstrawbs 11 ปีที่แล้ว +1

    have you never heard of a playlist ma'am?

  • @sachinnegi2161
    @sachinnegi2161 6 ปีที่แล้ว

    Sir is eigen vector and eigen space the same thing??

    • @karinerino
      @karinerino 6 ปีที่แล้ว

      did you even watch the video..

  • @andymitrop
    @andymitrop 5 ปีที่แล้ว +4

    I should be paying you 9K a year instead of my uni

  • @miketh6
    @miketh6 12 ปีที่แล้ว

    if you want to know which video came first you just go to kanacademy org

  • @imamnalog
    @imamnalog 13 ปีที่แล้ว

    @TheAncientScholar Thnx

  • @imatwink
    @imatwink 14 ปีที่แล้ว

    @HunterDX77M If you go to his website at khanacademy {dot} org then he has them in order and there is a link to the next video at the top of each video.

  • @imadElghourani
    @imadElghourani 14 ปีที่แล้ว

    @Lexorinox yupp

  • @taterichardson866
    @taterichardson866 8 ปีที่แล้ว +2

    Gah! " 'I' before 'E' except after 'C' "! Yet another word that breaks this rule! I guess we should also add "except, apparentlie, for words that sound like they're invented in Germanie".

  • @graei
    @graei 13 ปีที่แล้ว

    Why doesn't my lazy ass lecturer at uni explain things this simply..? >.>

  • @jimbaker5110
    @jimbaker5110 3 ปีที่แล้ว +2

    He uses a whole lot of words and sentences just to explain something very simple. It’s frustrating.

  • @Hershbomb
    @Hershbomb 12 ปีที่แล้ว

    possibly the best comment on this video...

  • @jimmy000
    @jimmy000 11 ปีที่แล้ว +1

    hahahaha, agreed!

  • @Karoke77
    @Karoke77 14 ปีที่แล้ว

    2+2=4.
    Am I ready???

    • @DavidBrit101
      @DavidBrit101 5 ปีที่แล้ว

      you first need to know 1 + 1 = 2

  • @russellkilgour
    @russellkilgour 12 ปีที่แล้ว

    I can't take him seriously...he sounds too much like Sips!

  • @pmecan
    @pmecan 13 ปีที่แล้ว

    Lin Alg Joke!
    What do you call an eigen-sheep?
    -
    -
    A LAMB! DUH!

  • @superjokerrr
    @superjokerrr 13 ปีที่แล้ว

    you talk so fast

  • @H1TMANactual
    @H1TMANactual 13 ปีที่แล้ว

    Well then after you learn the subject, make your own videos in non-bastardized English.