Linear Algebra Example Problems - Basis for an Eigenspace

แชร์
ฝัง
  • เผยแพร่เมื่อ 19 ธ.ค. 2024

ความคิดเห็น • 79

  • @donaldford2849
    @donaldford2849 3 ปีที่แล้ว +14

    Only two minutes in and I understood more things on this subject than in my actual classes keep it up .👍

    • @AdamPanagos
      @AdamPanagos  3 ปีที่แล้ว +1

      Thanks for the kind words, I’m glad you enjoyed the video! Make sure to check out my website adampanagos.org for additional content (600+ videos) you might find helpful. Thanks much, Adam

  • @malcolmcollinable
    @malcolmcollinable 8 ปีที่แล้ว +28

    When calculating the second null space the third row should be [-24 36 -24]. You left out the negative sign but put it there during calculation so answer is still correct.

    • @AdamPanagos
      @AdamPanagos  8 ปีที่แล้ว +3

      Yes, thanks so much. I just added an annotation to the video to note the mistake. Good catch!

  • @antoniaangelopoulou4269
    @antoniaangelopoulou4269 2 ปีที่แล้ว +1

    I have to thank youtube for teaching me Linear Algebra

  • @karandeepsinghchatha3872
    @karandeepsinghchatha3872 7 ปีที่แล้ว +2

    Hi Adam ! I like your videos very much followed them for my Linear Algebra course in year 1 of Engineering in Sweden.

    • @AdamPanagos
      @AdamPanagos  7 ปีที่แล้ว

      Excellent, glad to hear that! Good luck!

  • @marianne9317
    @marianne9317 6 ปีที่แล้ว +6

    Wonderful, simple explanation. Thank you!

  • @Red_Zealot
    @Red_Zealot 7 ปีที่แล้ว +7

    My textbook does A-(lambda)i while you do (lambda)i -A, does that matter?

    • @Triplechoco52
      @Triplechoco52 7 ปีที่แล้ว

      AKM Pros For comparison, mine is (lambda)i-A. IDK what yours is.

    • @donedumi-leslie5304
      @donedumi-leslie5304 7 ปีที่แล้ว

      Mine does A-lambdaI too.

    • @Triplechoco52
      @Triplechoco52 7 ปีที่แล้ว

      So it turns out they're both the same. It just one of those cases where they're equivalent by algebraic manipulation.

    • @donedumi-leslie5304
      @donedumi-leslie5304 7 ปีที่แล้ว +2

      Actually, maybe it doesn't matter. Both are gotten from Av = λv anyways.

    • @donedumi-leslie5304
      @donedumi-leslie5304 7 ปีที่แล้ว +1

      Jay G Sorry, I didn't see your reply before I commented again.

  • @ezrahinkley6132
    @ezrahinkley6132 7 ปีที่แล้ว +4

    great video dude, you explained a pretty complex topic really well and made it simple

  • @pyropower
    @pyropower 7 ปีที่แล้ว +2

    Thank you for this video. Was very well explained. I'm taking detailed notes for my upcoming quiz.

  • @supersonic174
    @supersonic174 6 ปีที่แล้ว +2

    is there any difference between an eigenvector and a bases for the eigenspace or are they the same thing

    • @AdamPanagos
      @AdamPanagos  6 ปีที่แล้ว +5

      They are different. An eigenvector is any vector x that satisfies the equation Ax = Lx where L is a scalar we call the eigenvalue associated with the eigenvector x.
      Since there are many vectors that satisfy this equation (e.g. an infinite number of them), we might be interested in compactly describing the entire collection of vectors that satisfy the equation Ax = Lx. That is exactly what a basis does.
      Remember, basis is a collection of vectors.
      If we have a basis for the eigenspace, any linear combination of the vectors in the basis also satisfies the equation Ax = Lx. Since we can't write down EVERY vector that satisfies the equation, writing down the basis for the eigenspace is kind of the next best thing since we then know what form a solution must have (e.g. it can be written as some linear combination of vectors in the basis).
      I hope that helps. Make sure to check out my website adampanagos.org for lots of additional content that you might find helpful. Thanks, Adam

    • @BoZhaoengineering
      @BoZhaoengineering 4 ปีที่แล้ว

      @@AdamPanagos thanks. just check what you said, all linear combination of eigenbasis is the (eigen)space/set satisfying the equation Ax=Lx(L is a scalar.)

  • @JenjenEatTheGalaxy
    @JenjenEatTheGalaxy 4 ปีที่แล้ว +1

    Very clear explanation, thanks!

    • @AdamPanagos
      @AdamPanagos  4 ปีที่แล้ว

      Glad to help, thanks for watching!

  • @MuhammadFaizan-br3cr
    @MuhammadFaizan-br3cr 4 ปีที่แล้ว +1

    Thanks my friend...you're a life saver

  • @fahimimtiaz2153
    @fahimimtiaz2153 2 ปีที่แล้ว +1

    thanks man keep producing the work! It was really helpful

    • @AdamPanagos
      @AdamPanagos  2 ปีที่แล้ว

      Thanks for the kind words, I’m glad you enjoyed the video! Make sure to check out my website adampanagos.org for additional content (600+ videos) you might find helpful. Thanks much, Adam

  • @elisesl7107
    @elisesl7107 2 ปีที่แล้ว

    thank you so much! MUCH better than my textbook:)

    • @AdamPanagos
      @AdamPanagos  2 ปีที่แล้ว

      I’m glad you enjoyed the video! Make sure to check out my website adampanagos.org for additional content (600+ videos) you might find helpful. Thanks, Adam

  • @oAbraksas
    @oAbraksas 7 ปีที่แล้ว +1

    shouldnt their inner product to be equals to zero if they form a basis? is not zero, but 1. It seems that im missing something

    • @AdamPanagos
      @AdamPanagos  7 ปีที่แล้ว +2

      A basis for a set of vectors does not necessarily have to be an orthogonal basis. The vectors found in this example are indeed a basis for the eigenspace since all vectors in the eigenspace can be written as a linear combination of the vectors (that is essentially the definition of a basis). One could enforce an orthogonal constraint as well, but that was not required/performed in this particular video. Hope that helps.
      Adam

    • @oAbraksas
      @oAbraksas 7 ปีที่แล้ว +1

      thank you!! It helped a lot, i had this question all day

  • @ryanveyr9195
    @ryanveyr9195 6 ปีที่แล้ว +1

    So wait after i find the associated eigenvectors for the eig. values, then i have shown the eigenspace? No need to write the solution? (i cant just leave it as you did). I'm taking Diff. Equations concurrently so i might be confusing methods or reasoning. It's pretty challenging to get used to

  • @dijahmasnawi6627
    @dijahmasnawi6627 5 ปีที่แล้ว +1

    how to find the dimensio correspond to the eigenspace?

    • @dijahmasnawi6627
      @dijahmasnawi6627 5 ปีที่แล้ว

      help me senpaiiii

    • @AdamPanagos
      @AdamPanagos  5 ปีที่แล้ว

      The number of vectors in the basis is the dimension of the space. So, if we find that a space can be represented with 3 vectors as the basis, the space has a dimension of 3. Hope that helps,
      Adam

  • @sharonselvi6099
    @sharonselvi6099 2 ปีที่แล้ว

    for the second λI-A last, on column 1 line 3, its supposed to be -24 right? then x1=x3

  • @mauricioperedo9657
    @mauricioperedo9657 2 ปีที่แล้ว +1

    Great video! Many thanks

    • @AdamPanagos
      @AdamPanagos  2 ปีที่แล้ว +1

      You're very welcome, thanks for watching. Make sure to check out my website adampanagos.org for additional content (600+ videos) you might find helpful. Thanks, Adam.

  • @Kim-Yo-Jong123
    @Kim-Yo-Jong123 ปีที่แล้ว +1

    Thank you

  • @UifaleanAlexandru
    @UifaleanAlexandru 4 ปีที่แล้ว +1

    Clear and concise explanation! Thank you!
    Does the same process apply if we have complex eigenvector and we want to create real basis from it?

  • @madhirajutrisha9240
    @madhirajutrisha9240 3 ปีที่แล้ว

    So eigenbasis I.e basis of eigenvectors are just the resultant eigenvectors we get right ?!?

  • @shayandurrani3738
    @shayandurrani3738 2 ปีที่แล้ว

    Thanks for the video. That was easy to understand. In the last part why we did row reduction? Can anyone can answer? Thanks

  • @dismasyves
    @dismasyves 3 ปีที่แล้ว +1

    Thank you! It helped a lot.

    • @AdamPanagos
      @AdamPanagos  3 ปีที่แล้ว

      Glad I could help, thanks for watching. Make sure to check out my website adampanagos.org for additional content (600+ videos) you might find helpful. Thanks, Adam

  • @jamesa.646
    @jamesa.646 4 ปีที่แล้ว

    can the null space of number two also be [1,0,-1] or is [-1,0,1] the only right answer?

    • @AdamPanagos
      @AdamPanagos  4 ปีที่แล้ว +1

      Yes, x3 is a free variable so we can choose any value we want. I selected x3 = 1. If you select x3 = -1 you'll get the answer you proposed. Hope that helps,
      Adam

  • @mortuiambulante4683
    @mortuiambulante4683 4 ปีที่แล้ว +1

    This video helped me a fuck ton, I wish I could hug you, the whole x3 can be any value thing was so hard to grasp for me //Swedish mechanical engineerstudent

  • @GaryTugan
    @GaryTugan 3 ปีที่แล้ว

    excellent vid. hey, so on that last eigenvector.... since we traditionally do NOT use fractions or decimal numbers in our choice, then by choosing for X2 to be = 2, then X1 = 3. so instead of an awkward (1.5, 1, 0), we can use (3, 2, 0). At least in my years of doing this, I've noticed the latter to be the trend. curious, was this NOT part of what you were taught?

    • @AdamPanagos
      @AdamPanagos  3 ปีที่แล้ว

      Either is fine. The direction is all that matters. Hope that helps,
      Adam

    • @jacmac225
      @jacmac225 ปีที่แล้ว

      Not gonna lie, chief: ya went a little heavy on the snobby tone on this one x.x

    • @GaryTugan
      @GaryTugan ปีที่แล้ว

      @@jacmac225 was a straight up question. your sensibilities harmed by questions...?

  • @jonathanmilloway7345
    @jonathanmilloway7345 2 ปีที่แล้ว

    Is it not supposed to be A-lambda*I?

    • @AdamPanagos
      @AdamPanagos  2 ปีที่แล้ว

      With way is fine, you'll get the same answer since we're setting equal to zero. A-LI = 0 or LI-A = 0 are the same. Hope that helps,
      Adam

  • @cristianadias8013
    @cristianadias8013 7 ปีที่แล้ว +1

    Thank you sir for this amazing video!

    • @AdamPanagos
      @AdamPanagos  6 ปีที่แล้ว

      Glad you liked it, thanks!

  • @naeemjamali1475
    @naeemjamali1475 4 ปีที่แล้ว +2

    In my University's book it is A-(lambda)I.

    • @AdamPanagos
      @AdamPanagos  4 ปีที่แล้ว +8

      It ends up being the same thing. We're solving an equation that's equal to zero. So, you can write the equation either way, since we can multiply an equation equal to zero by negative 1 on each sides without changing the solution. Hope that helps,
      Adam

    • @poecoreface
      @poecoreface ปีที่แล้ว

      @@AdamPanagos helped me thanks

  • @sidmukhtadir6837
    @sidmukhtadir6837 5 ปีที่แล้ว

    so eigenspace and eigenvectors are the same thing?

    • @AdamPanagos
      @AdamPanagos  5 ปีที่แล้ว +2

      No, not quite. An eigenvector x is just a vector that satisfies Ax = Lx. The span of all eigenvectors is the eigenspace.

    • @GaryTugan
      @GaryTugan 3 ปีที่แล้ว +1

      @@AdamPanagos Thanks! THAT for sometime finally made sense to me out of all I've been reading about the topic. Nice and concise and makes logical sense too.

    • @AdamPanagos
      @AdamPanagos  3 ปีที่แล้ว

      @@GaryTugan You're very welcome, thanks for watching. Make sure to check out my website adampanagos.org for additional content (600+ videos) you might find helpful. Thanks, Adam.

  • @PokeShadow77
    @PokeShadow77 4 ปีที่แล้ว

    In the final part, isn't x2 free and x3 = 1 since the columns are what correspond to each variable value? Otherwise, great stuff!

    • @GaryTugan
      @GaryTugan 3 ปีที่แล้ว

      yes, x2 IS the free variable. which is why he solved for x1 in terms of x2. When a variable (x1 or x2 or x3, etc.) is the free variable, we then write the others in terms of that.

  • @collincypret1983
    @collincypret1983 3 ปีที่แล้ว +1

    thank you I was losing my mind.

    • @AdamPanagos
      @AdamPanagos  3 ปีที่แล้ว

      Glad I could help, thanks for watching. Make sure to check out my website adampanagos.org for additional content (600+ videos) you might find helpful. Thanks, Adam

  • @derrick_rj.5035
    @derrick_rj.5035 11 หลายเดือนก่อน

    isnt it A-(lamda*x)

  • @hfuytuyuyu6348
    @hfuytuyuyu6348 2 ปีที่แล้ว +1

    「ビデオサウンドは、私の想像を超えて、かなり良いです」、

  • @mutludogan5408
    @mutludogan5408 4 ปีที่แล้ว +1

    thank youu

  • @roboter8024
    @roboter8024 5 ปีที่แล้ว +1

    thxxx

    • @AdamPanagos
      @AdamPanagos  5 ปีที่แล้ว

      You're welcome, thanks for watching. Make sure to check out my website adampanagos.org where I have lots of other material you might find helpful. Thanks,
      Adam

  • @DAMfoxygrampa
    @DAMfoxygrampa 6 ปีที่แล้ว +2

    I love you