Basis and Dimension

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  • čas přidán 23. 04. 2019
  • Now we know about vector spaces, so it's time to learn how to form something called a basis for that vector space. This is a set of linearly independent vectors that can be used as building blocks to make any other vector in the space. Let's take a closer look at this, as well as the dimension of a vector space, and what that means.
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Komentáře • 152

  • @ChocolateMilkCultLeader
    @ChocolateMilkCultLeader Před 4 lety +500

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      @finnegandylan800 Před 2 lety +2

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  • @quantumleap7964
    @quantumleap7964 Před rokem +13

    wow, these last couple of videos of the playlist help make a complete comprehensive overview of the ideas need to learn tensor algebra and tensor calculus. This is a must watch for any General Relativity student

  • @christycaroline3697
    @christycaroline3697 Před 3 lety +55

    The way you explain is wonderful. I'm glad I found you. I was breaking my head with these concepts, now it's all clear. Thanks a million for making it EASY. :) God bless.

  • @michaelpisciarino5348
    @michaelpisciarino5348 Před 5 lety +212

    0:27 A Basis
    1:31 Check Linear Combination
    2:26 Span
    2:52 Satisfying Linear Independence
    3:21 A more complicated example (R 2x2)
    3:54 Span check
    4:23 Distribute the Scalars. Add up the new matrix.
    4:45 Make sure a solution exists
    5:43 Check Linear Independence
    6:57 Row Echelon Form:
    - No Free Variables
    - All Scalars must be = 0
    7:34 Both conditions verified ✔️
    Basis With N Elements= Dimension N
    9:05 Check Comprehension

  • @perspicacity89
    @perspicacity89 Před rokem +5

    Wow! Thank you so much! Your videos are so simple, easy to understand, and concise! Thank you!

  • @mmbpaja2190
    @mmbpaja2190 Před 3 lety +6

    Thank you for explaining this topic so clearly. 💕

  • @margaretnmaju1982
    @margaretnmaju1982 Před rokem +2

    Professor Dave has really helped me and still helping me

  • @user-pe1we2jp3j
    @user-pe1we2jp3j Před 3 lety +5

    Wow u are an awesome tutor. I easily learned the topics in 1 hour instead of 24 hours of nonsense thank u so much😊😊😊😊

  • @immortalspiritualbeing7037

    very clear explanation and examples,thank you !

  • @jingyiwang5113
    @jingyiwang5113 Před rokem +1

    Your video is amazing! I finally understand this point. Thank you so much!

  • @michaeltheisen
    @michaeltheisen Před 2 lety +3

    Thank you for explaining this so straight forward and to the point.

  • @erikross-rnnow5517
    @erikross-rnnow5517 Před 2 lety +8

    Basis vectors/Matrices seemed so far out of reach even after trying to understand them for a couple of weeks but after this video, which make them seem easy, I think I finally understand them. Thanks Dave! :))

  • @b.cmagwaza6365
    @b.cmagwaza6365 Před 4 lety +50

    you saved my life, linear algebra wanted me not to graduate

  • @sushmareddy5129
    @sushmareddy5129 Před 3 lety

    Very easy to understand..Thanks for the video🙏

  • @tidalfriction5301
    @tidalfriction5301 Před 3 lety

    This was incredible and clear bro!!!

  • @sekharp3305
    @sekharp3305 Před 2 lety +1

    Thanks a lot for sharing your knowledge. Your explanation is good. It would have been better if you have included explanation of the question and answers also.

  • @nikitabhatt5246
    @nikitabhatt5246 Před 3 lety +1

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    @hemanthkotagiri8865 Před 5 lety +21

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  • @christinenalwoga6008
    @christinenalwoga6008 Před 3 lety

    I never imagined that I would ever understand linear algebra. Thanks bro

  • @md_hyena
    @md_hyena Před 5 lety +3

    Thank You! Can't wait for a video about a uniform space and tensors; I repent, I never truly understood them.

  • @Mark-nh2vh
    @Mark-nh2vh Před 6 měsíci +1

    Dave single handedly educated half a million people in 10 minutes

  • @nihaalsinghbhogal4837
    @nihaalsinghbhogal4837 Před 2 lety

    Thanks Professor Dave! ❤

  • @anandbhamashetti9730
    @anandbhamashetti9730 Před měsícem

    Great video. Very clear. With gratitude from india

  • @meghanakrishna6190
    @meghanakrishna6190 Před rokem

    these r so helpful and great !! helping me survive thru college 😄😁

  • @Abdulrahman-hb6fy
    @Abdulrahman-hb6fy Před 3 měsíci +1

    I have a sweet information
    When n (number of columns) is not equal to m (number of rows) then the set is always not a basis (if the question ask if a specific set of vectors is a basis or not)
    but when n = m, then you have two possibilities depending on the det(A), in other words:
    det(A) is equal to 0 ==> the set is not a basis
    det(A) isn't equal to 0 ==> the set is a basis

  • @leonardoguzman7854
    @leonardoguzman7854 Před rokem +1

    I literally understood something that my professor has been explaining for two weeks in just 10 minutes. Thanks!

  • @danah81
    @danah81 Před 8 měsíci

    YOU ARE SAVING MINE AND MY ROMMAMTES FUTURES THX

  • @kmishy
    @kmishy Před 3 lety

    Can we expect a subspace who span vector space but vectors (elements ) in that subspace are linearly dependent?

  • @Soyokaze-if7kp
    @Soyokaze-if7kp Před měsícem

    I already gave a like as soon as I saw the intro

  • @anthonyfaddul3582
    @anthonyfaddul3582 Před 7 měsíci +1

    this guy is actually the goat

  • @parasuramang1860
    @parasuramang1860 Před 5 lety +5

    Please send reference books, websites that you use... That would be helpful.

  • @dter706
    @dter706 Před 3 lety +3

    The reduced row echelon form isn't finished yet at 7:22, you can still do R3+R4, R2-R4 and after that R1-R3 which doesn't require you to solve the remaining set of equations.

    • @johanjimenez1249
      @johanjimenez1249 Před 3 lety +2

      You don't need to since you can see c4 is equal to zero which would then make the rest zero.

  • @fredhasopinions
    @fredhasopinions Před 3 lety

    sir, you're a hero, jesus christ you have no idea how doomed i'd be without this video right now

  • @tenex0630
    @tenex0630 Před 5 lety +1

    Thanks for teaching me Newton's Laws!
    ~We love your work

  • @ilong4rennes
    @ilong4rennes Před rokem

    tysm!!!!!! you saved my life!!

  • @flamesage6796
    @flamesage6796 Před rokem

    Do free variables effect whether or not the basi can be linearly independent?

  • @advancedappliedandpuremath
    @advancedappliedandpuremath Před měsícem

    Sir can we find the null space of set of vectors from M2x2 like we do for vectors in R^n

  • @amitmishra-fe6yi
    @amitmishra-fe6yi Před 3 lety

    Really very good contain 🙏🏽

  • @bryananthonyangouw4045

    so good
    thank you

  • @olgachervonyuk4993
    @olgachervonyuk4993 Před rokem

    Wonderful theme

  • @thesoccer10ful
    @thesoccer10ful Před 3 lety +4

    5:05 since you’re taking the determinate of the square matrix and it’s a none zero number, isn’t also linearly independent too?

  • @tamizhazhagan-jaishreekris2199

    Superb 😃😃

  • @aleksanderaksenov1363
    @aleksanderaksenov1363 Před 3 lety

    but the main question is-why the canonical basis is indexed by natural numbers?And can we describe canonaical basis in terms of matrices?

  • @Richard___554o
    @Richard___554o Před 2 dny

    Hello, I have some delightful news that will brighten your day!

  • @bernab
    @bernab Před 4 lety +3

    I think the first 3 vectors is because for a R2, one need only 2 vectors for creating a base for R2. Plus, 3,2 could be 2 times the 1,0. Right?

  • @farukakan8465
    @farukakan8465 Před 3 lety

    Good expression , thanks 🇹🇷

  • @ditya3548
    @ditya3548 Před 2 lety

    thanks a lot!

  • @subhrasarkar3155
    @subhrasarkar3155 Před 4 lety +1

    Thanks

  • @anshedits2167
    @anshedits2167 Před 9 měsíci

    2 v + 3 w.. In this v and w are vectors and these are basis as well?

  • @mikakk2330
    @mikakk2330 Před 4 lety +50

    why do professors make everything seem harder...?

    • @muhammadzaid308
      @muhammadzaid308 Před 3 lety +1

      I wish I knew....

    • @joeysmith5767
      @joeysmith5767 Před 3 lety +12

      They feel like they have to fill up the lecture time that was assigned and they end up stretching the material out in a complex way to fill the time

    • @gemy6188
      @gemy6188 Před 3 lety +5

      It's about Talent and the different criteria, some have the knowledge but they haven't the capability to deliver this knowledge.

    • @kmishy
      @kmishy Před 3 lety +1

      @@gemy6188 In India we could also talk about lack of knowledge and poor delivery skills

    • @swavekbu4959
      @swavekbu4959 Před 2 lety +3

      Two reasons: 1. They don't know how to teach and don't have a firm grasp of the subject themselves. 2. They want to confuse you so that fewer people have mastery of the knowledge. The less you know, the more they know, and people with big egos want to have "specialized" knowledge that is not accessible to others. Write a book nobody understands, and claim yourself a genius.

  • @samueltoluwani8405
    @samueltoluwani8405 Před 3 lety +1

    For the first question in the comprehension part, 0 is the determinant, so that should be linearly dependent right?

  • @user-ih7iq6bw5o
    @user-ih7iq6bw5o Před 2 lety

    You are a godsend

  • @ummehabiba7430
    @ummehabiba7430 Před 3 lety

    Linear independent vectors means we cant take linear combination of them...on the other hand span is all the linear combination of those vectors. Basis is the vectors will be linearly independent + they will span. I am confused...how these 2 can be true at the same time?

  • @dddhhj8709
    @dddhhj8709 Před 2 lety

    superb ....

  • @Starkeweg
    @Starkeweg Před rokem

    what if instead of all leading ones we had a leading 2 in some position. thats okay right ?. since its not Reduced row echelon form

  • @iced751
    @iced751 Před 2 lety +1

    At 5:26 how is the determinant 1? Cause multiplying the 4 brackets above from the formula (ad-bc) gets: 0, 0, 1, then the last one is 0-1 which is -1

    • @egeyesilyurt3701
      @egeyesilyurt3701 Před rokem

      doesnt matter regardless, if the det isnt equal to 0 we can proceed

  • @user-tl6ry9kv8d
    @user-tl6ry9kv8d Před 5 lety +1

    Thx

  • @yourmathtutor5130
    @yourmathtutor5130 Před 3 lety +1

    What if such cases when determinant is zero yet it has infinitely many solutions?

  • @rahulsreedharan1922
    @rahulsreedharan1922 Před 3 lety

    If they are linearly independent, it means there are no linear combinations among the vectors. So, how can a basis have two conditions where (1) they are linearly independent and (2) they span the vector space V (by a linear combination of the vectors), don't the conditions contradict each other? Please clarify, and let me know if I'm missing something here.

    • @sahilkhurana6941
      @sahilkhurana6941 Před 3 lety +1

      Dude ! Linearly independent does not mean that they will have no linear combination its actually satisfies that they can have linear combination coz we check that the vectors are not dependant so that we can have all the possible linear combination!

    • @RahulSharma-oc2qd
      @RahulSharma-oc2qd Před 3 lety +2

      Linear combination and linear dependent is two different things. Whether given two vector elements within the vector space are linearly dependent or not has to do nothing with the linear combination. Any set of vector elements can be written as linear combination (with respect to their coefficients)

  • @BlueLily-kx7mz
    @BlueLily-kx7mz Před rokem

    But Im not getting the determinant value as 1 in example 2 while checking for spaning 5.23 ...
    Can somebody please help.... please...

  • @swagatggautam6630
    @swagatggautam6630 Před rokem +1

    For R 2X2 matix, can't we just say that the matices are linearly independent as their determinant is not equal to zero.
    We created the matrix 4X4 which is a square matrix and its determinant is 1, so it satisfies that they are linearly independent.!!!

  • @tamannashaikh2712
    @tamannashaikh2712 Před 3 měsíci

    Can somebody please help me? In the previous video where we had to check whether a matrix is linear independent or not by row operation, we didn't get all 1's in the main diagonal. But in this video why do I have to get all one's in the main diagonal?

    • @karthi6548
      @karthi6548 Před 3 měsíci

      works either way, i think

    • @karthi6548
      @karthi6548 Před 3 měsíci

      because all we aim is to reduce the variables

  • @jellyfrancis
    @jellyfrancis Před 2 lety

    How to apply curl to higher dimensional vector field

  • @95yahel
    @95yahel Před 2 lety +1

    How can you have more than a dimension of 3 in a 3D space? Wouldnt any more vectors are just repetitive and therefore be linearly dependent?

    • @ProfessorDaveExplains
      @ProfessorDaveExplains  Před 2 lety +2

      Mathematics isn't limited to the three spatial dimensions we are familiar with, it can utilize many more. We just are incapable of visualizing it.

  • @terekafaw9463
    @terekafaw9463 Před rokem

    1. The dimension of the matrix is
    2. In the matrix , the entry in the third row and second column is _____.
    3. For what values of and , the two matrices are equal?______
    4. Write a diagonal matrix of order two, such that the entries on the diagonal zero._______
    5. Given the following matrices and , then compute
    a) b) c) d) e) f)
    6. Find the products of a row matrix and the column matrix ; that is and YX.
    7. A manufacturer produces three products: A, B, and C, which he can sell in two markets. Annual sales volume is indicted as follows.
    Product A B C
    Market I 10,000 units 2,000 units 80,000 units
    Market II 6,000 units 20,000 units 8,000 units
    a) If unit sales of A, B, and C are 2.50 Birr, 1.25 Birr, and 1.50 Birr, respectively, find the total revenue as a product of matrices in each market.
    b) If unit sales of A, B, and C are 1.80 Birr, 1.20 Birr, and 0.80 Birr, respectively, find the gross profit as a product of matrices in each market
    pleas do you make this

  • @theojunming
    @theojunming Před rokem

    Isnt the set of vectors rank 4 ? How can a rank 4 span R2

  • @warfyaa6143
    @warfyaa6143 Před 5 lety +1

    cool haircut and nice video .

  • @codeworld420
    @codeworld420 Před rokem

    in the comprehension, how the first one is not linearly independent ?

  • @RohitKumar-zp6ci
    @RohitKumar-zp6ci Před rokem

    Can anyone provide me solution of last 2 questions?

  • @kontiimanalatit8987
    @kontiimanalatit8987 Před 11 měsíci

    Doesn't the det of matrix being 1 (not 0) means its elements are linearly independent (so we don't need to form row echelon form)

    • @Yuu.riishii
      @Yuu.riishii Před 10 měsíci

      I agree with this.

    • @nark4837
      @nark4837 Před 7 měsíci

      also, can you confirm that there is no point in ever checking both conditions for basis, i.e., condition 1: spanning, condition 2: linearly independent?
      if you know it spans and number of vectors > number of dimensions, it can't be a basis.
      if you know it spans and number of vectors = number of dimensions, it MUST be a basis.
      if you know number of vectors < number of dimensions, it can't span?
      you might as well just manually look, saves you work

  • @tomatrix7525
    @tomatrix7525 Před 2 lety +1

    This is a godsend. Ya boy thought he was fucked for midterm

  • @AS-ds4in
    @AS-ds4in Před 2 lety

    6:36
    how can we multiply R3 by -1
    wont it change the equation??

    • @AS-ds4in
      @AS-ds4in Před rokem +2

      Found this comment 6 months later and now i know the answer
      if we multiply both sides of an equation it will still remain the same equation and is valid
      here the other side of the equation(right of =) is 0 and 0 multiplied by anything gives 0 so we dont include it

  • @azammozaffarikhah26
    @azammozaffarikhah26 Před rokem

    thank you, can you give me a vector space with infinite dimensions?

  • @maxingout6124
    @maxingout6124 Před rokem

    He unlocked the 4th dimension 👀

  • @momenabubasha7060
    @momenabubasha7060 Před rokem

    why is the first one not a basis in the comprehension

  • @kotikunja7583
    @kotikunja7583 Před 3 lety

    Professor, vector space with the only vector "zero vector" has dimension 1. 8:23

  • @Christian-mn8dh
    @Christian-mn8dh Před rokem

    4:54

  • @ultimateboss5161
    @ultimateboss5161 Před 2 měsíci

    Your explanation is good but you didnt explain the type of questions in the check comprehension

  • @jestinaluvanda-jm4tc
    @jestinaluvanda-jm4tc Před rokem

    Move words passing through a video when you are explaining

  • @patrick-zb6fx
    @patrick-zb6fx Před 2 lety

    thank you linear algebra jesus.

  • @zilunhe8191
    @zilunhe8191 Před rokem

    Save my life

  • @OP-yw3ws
    @OP-yw3ws Před 2 lety

    why aren't u my college professor 😭

  • @ToanPham-wr7xe
    @ToanPham-wr7xe Před 5 měsíci

    😮

  • @GoogleUser-nx3wp
    @GoogleUser-nx3wp Před 2 lety

    What happend to your hair prof ?

  • @topiado2073
    @topiado2073 Před 4 lety +1

    Sir ua so handsome

  • @ethiopiandishtechnotian

    Pls help me?

  • @FootLettuce
    @FootLettuce Před 3 lety

    Stop watching anime brother.
    We must fight the MPLA.
    (Matrices Projections Linear Algebra)

  • @justthenamekevin
    @justthenamekevin Před 2 lety

    in french: span is engendré!!!

  • @rossfriedman6570
    @rossfriedman6570 Před 9 měsíci

    Sahh dude

  • @is6815
    @is6815 Před 5 lety +1

    1st to comment!

  • @honestdudeguru
    @honestdudeguru Před 2 lety

    I am disappointed...I sent you an email two weeks ago. No response from you yet.

  • @siddharthkumar4440
    @siddharthkumar4440 Před rokem

    I miss the jesus version 😂😂

  • @lakshaysharma2116
    @lakshaysharma2116 Před rokem

    There is god and he is an American

  • @cho.gath789
    @cho.gath789 Před 4 lety +1

    Dude... Every 5 seconds you pause for like 3 seconds.... then we all get to hear you take a deep breath and talk for 5 more seconds, then pause again. You need to just relax and talk like you are in a conversation.

    • @ProfessorDaveExplains
      @ProfessorDaveExplains  Před 4 lety +43

      No. The pacing is deliberate for those who need time to process what's on the screen. Teaching math is not a conversation.

    • @aryanks2167
      @aryanks2167 Před 4 lety +17

      The pacing is all good to me

    • @farhatfatima1168
      @farhatfatima1168 Před 2 lety

      @@ProfessorDaveExplains yes you are right sir