Lecture 1: The Column Space of A Contains All Vectors Ax

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  • čas přidán 15. 05. 2019
  • MIT 18.065 Matrix Methods in Data Analysis, Signal Processing, and Machine Learning, Spring 2018
    Instructor: Gilbert Strang
    View the complete course: ocw.mit.edu/18-065S18
    CZcams Playlist: • MIT 18.065 Matrix Meth...
    In this first lecture, Professor Strang introduces the linear algebra principles critical for understanding the content of the course. In particular, matrix-vector multiplication Ax and the column space of a matrix and the rank.
    License: Creative Commons BY-NC-SA
    More information at ocw.mit.edu/terms
    More courses at ocw.mit.edu

Komentáře • 266

  • @tchappyha4034
    @tchappyha4034 Před 5 lety +492

    The greatest math teacher in the world now teaches Data analysis, Signal Processing and Machine Learning! Thank you very much!

    • @frankbreeze9895
      @frankbreeze9895 Před 5 lety +9

      I cannnot agree with you more. I think hundreds of thousands of people have benefited from this great teacher!

    • @colinmaharaj
      @colinmaharaj Před 4 lety +3

      @@frankbreeze9895 That means you can agree with him more :)

    • @guohaodu5713
      @guohaodu5713 Před 4 lety +2

      @@frankbreeze9895 that's right!

    • @piotrek0207
      @piotrek0207 Před 3 lety

      Right :)

  • @_nttai
    @_nttai Před 3 lety +33

    I can't believe I'm watching this for entertainment at my own will. He's probably the greatest math teacher I've ever had

  • @TheFrygar
    @TheFrygar Před 4 lety +16

    omg it's snowing outside and these kids are sitting in a nice cozy room listening to one of the greatest linear algebra teachers in the world...I think I could die happy after such an experience

  • @xeneseken
    @xeneseken Před 5 lety +248

    It is snowing at the outside at 4:58. what a wonderful and lovely class.

  • @jerrymahone335
    @jerrymahone335 Před 5 lety +139

    Dr. Strang is a national treasure.

    • @ekbastu
      @ekbastu Před 4 lety +16

      international

    • @RC-bm9mf
      @RC-bm9mf Před 3 lety +10

      Universal, I mean, literally in the universe.

    • @senwang1982
      @senwang1982 Před 3 lety +3

      human's treasure

    • @vithaln7646
      @vithaln7646 Před 3 lety +2

      may be universal , entire world watch him

  • @kavanavvasishta4692
    @kavanavvasishta4692 Před 5 lety +153

    I was just watching his 2005 video lectures of Linear Algebra and I suddenly got to this lecture. I don't know why but it broke my heart to see Prof. Strang aged so much. Such a lovely human!

  • @wibirama
    @wibirama Před 3 lety +60

    Prof. Gilbert Strang's videos had helped me during my M.Eng. study, I watched him once again in 2011-2014 during my PhD. Last year I got his new book, and today I am watching (again) he is teaching linear algebra for data analysis, signal processing and machine learning because I have to teach Fundamentals of AI for my undergrad students. Thank you so much Prof. Strang, you are my best online mentor in mathematics!

  • @tcveatch
    @tcveatch Před 11 měsíci +2

    I like the feeling of watching the snow come down as we learn the comfortable and warm truth of things, in a safe kind classroom where careful work brings predictable success. The earnest student has faith that study will indeed bring learning, despite the cold and snowy world outside.

  • @zkhandwala
    @zkhandwala Před 5 lety +17

    At 84 years of age, he continues to be a maverick in the world of math education. Inspiring, to say the least.

  • @jonahansen
    @jonahansen Před 5 lety +31

    Gotta hand it to Dr. Strang! He's still going strong and loves doing it. Those students and all viewers of these videos should consider themselves lucky...

  • @Zonnymaka
    @Zonnymaka Před 5 lety +56

    24:38 16*(first row) -9* (second row)= (third row)
    Welcome back Doc Strang!

    • @allergictoalliteration6033
      @allergictoalliteration6033 Před 4 měsíci

      Thank you! How do you derive it? Is it just through trial-and-error with different combinations? Or is there a better/more intuitive approach?

    • @Zonnymaka
      @Zonnymaka Před 4 měsíci

      @@allergictoalliteration6033 Just take the first 2 rows and turn them into 2 columns (call the resulting (3x2) matrix A). Then solve Ax=b where b is the third row turned into a (3x1) vector.

  • @javiervalenciagoujon5888
    @javiervalenciagoujon5888 Před 5 lety +24

    The best linear algebra teacher in the world now is going to teach us how to apply this concepts in real world problems . I can't thank enough MIT OCW and professor Strang for this.

  • @gongfei
    @gongfei Před 5 lety +61

    4:42 A multiply x, matrix A times vector x, how to look at that, think of the *rows* , combination of the vectors
    8:56 column space of A, C(A)
    18:31 C: the basis of A's column space
    20:00 the column rank of A
    20:22 A= C times R, factoring
    23:49 column rank = row rank

  • @jdoesmath2065
    @jdoesmath2065 Před 2 lety +9

    As someone who has studied mathematics for 40 years and taught mathematics for 30 years, I can say that Professor Strang's wisdom and insight is amazing. Moreover, his ability to share this insight with enthusiasm (however quirky and geeky) is a gift to all of us. Thank you Sir. Bless all those dedicated to teaching.

  • @seamus9898
    @seamus9898 Před 5 lety +69

    Glad to see he's well!
    Much better than the 240p quality of the original linear algebra videos.

    • @raitup00
      @raitup00 Před 5 lety +1

      Agree! What a difference!

    • @victorsung3582
      @victorsung3582 Před 5 lety +6

      The content in his original lectures are still amazing! :)

    • @gongfei
      @gongfei Před 5 lety +5

      @@victorsung3582 the video resolution doesn't matter at all.

  • @BleachWizz
    @BleachWizz Před 3 lety +7

    27:00
    To find the combination you're going to scale the first one by a and the second one by b, then try to find c:
    From first column: 2a+3b=5
    From second column: a+b=7
    Working on first:
    2(7-b)+3b=5
    b=5-14=-9
    Working on second:
    a=7-(-9)=16
    So:
    16.r1 - 9.r2 = r3

    • @apetrenko_ai
      @apetrenko_ai Před 2 lety

      Thank you, was looking for this comment!🙂

    • @CardiganBear
      @CardiganBear Před rokem +1

      Or, find the reduced row echelon form of the transpose matrix = [1 0 16, 0 1 -9, 0 0 0]. Tells you that you need 16 of col 1 (originally row 1) minus 9 of col 2 (row 2) to make col 3 (row 3).

  • @rashidissa5887
    @rashidissa5887 Před 2 měsíci

    I don't understand anything here, but I'm fascinated watching you,Sir. I only have an O-Level maths (1967) Cambridge but still following up lessons in the U-tube for the love of the subject

  • @madmanzila
    @madmanzila Před 5 lety +17

    Much respect To Professor Gilbert Stang.

  • @semtex6412
    @semtex6412 Před rokem +1

    who else is here to reminisce the past with this awesome professor? 66 years of MIT!

  • @gabriellaugusto
    @gabriellaugusto Před 5 lety +5

    Finally this course has been release in MIT OCW! Thank a lot!

  • @pranayc94
    @pranayc94 Před 4 lety +1

    It’s so refreshing to see Prof.Strang teaching again. Man what an exiting adventure.

  • @jen-lichen8163
    @jen-lichen8163 Před 4 lety +1

    With this awesome tutorial and maybe one of the most passionate professors I've ever seen, even the snow outside the window seems to show some Christmas feelings.

  • @skilambi
    @skilambi Před 3 měsíci

    He's a realized soul!!! Not less than a saint. How many people have benefitted from this great mind! I cannot thank him enough.

  • @IrfanAli-mo6mh
    @IrfanAli-mo6mh Před 5 lety +17

    Thanks for opencaourseware that we can learn from this legend of Linear Algebra....

  • @basit005
    @basit005 Před 5 lety +16

    I got his linear algebra book in 2011, never really finished it as I had graduated and got into different things. Out of curiosity I started this video, it seems like Strang's hands are shaking and twitchy. I didn't realize he had gotten this frail and old, but its interesting to see that the mind is still as sharp as a razor edge. He has done a lot with his life and I hope that people who watch this lecture series go on to carry his legacy when he isn't around any more :')

  • @saratbhargavachinni5544
    @saratbhargavachinni5544 Před 5 lety +1

    Very excited to learn one more Video course from Prof Gilbert Strang, One of the best teachers I have ever had!!

  • @yanfengliu
    @yanfengliu Před 5 lety

    Wow all the concepts make so much more sense now. Dr. Strang really is a great teacher!

  • @EDUARDOCAPANEMAecapanema
    @EDUARDOCAPANEMAecapanema Před 2 lety +1

    This Professor is simply amazing. So humble to teach and so thorough. Thanks for this!

  • @xingjieli3069
    @xingjieli3069 Před 2 lety

    It's great to revisit all linear algebra from a different point view! It really opens my mind! Thank you Professor Strang!

  • @amruthgadag4813
    @amruthgadag4813 Před 3 lety +1

    A mesmerizing amazing person ever. I am really astonished to see his dedication to linear algebra. A big salute to him.

  • @user-ef3ej4pq4f
    @user-ef3ej4pq4f Před 5 lety +3

    Although I have learnt Linear Algebra in last semester, Still feeling refreshed and amazed watching these lectures, Dr. Strang's teaching skill is sooo good!!!

  • @realworld8690
    @realworld8690 Před 4 lety

    Following his lectures since 2017, greatest teacher .

  • @alexandrefelicio3902
    @alexandrefelicio3902 Před 4 lety

    Professor Strang is absolutely amazing! The best math teacher I have ever seen!

  • @user-uq7ri1pz2c
    @user-uq7ri1pz2c Před 3 lety

    Gilbert Strang, thank you very much for everything you have done for us. You are the best teacher I have ever met

  • @romanbesel4759
    @romanbesel4759 Před 3 lety

    Absolutely fantastic! Such a pleasure to learn about this interesting topic by a gifted teacher like Gilbert Strang.

  • @kellypainter7625
    @kellypainter7625 Před 5 lety +1

    Prof. Strang is such a good teacher. Awesome.

  • @deeprecce9852
    @deeprecce9852 Před 4 lety

    Absolutely delightful to see another of Prof Strang lectures...,
    PS A busy and working minds is like a brain exercise that will keep you mentally healthy for a long long time!!

  • @dennisestenson7820
    @dennisestenson7820 Před 2 lety +1

    I watched his 18.06 lectures online in the mid 2000's and it left a deep impression on me. I am so happy to see he's still teaching and share his excitement about him teaching this course.

  • @reneeliu6676
    @reneeliu6676 Před 5 lety +24

    Thank you Professor Strang! I am going to get up early tomorrow morning and watch this video with the best part of my day!
    I also need to buy a super expensive notebook only for Professor Strang's class!

  • @arvindkumar2174
    @arvindkumar2174 Před 5 lety +2

    Thank You very prof. strang for this lectures. I always thought if prof. strang would have taught this lectures then it would be the best. Now we have this. Now I will get up early and my first task will be to complete prof. strang lectures. Thank You very much professor. Be healthy and long live.

  • @junyan6445
    @junyan6445 Před 5 lety +4

    I really respect Prof. Gilbert Strang!

  • @tdchayes
    @tdchayes Před 5 lety +7

    24:00 The combination of rows is 16*row1-9*row2-row3=0

  • @EvanZamir
    @EvanZamir Před 5 lety +2

    Thank you for these lectures, Dr. Strang.

  • @piotrek0207
    @piotrek0207 Před 3 lety +3

    Thank you MIT OCW for sharing knowledge.

  • @georgesadler7830
    @georgesadler7830 Před 2 lety

    DR. Strang thank you for a fantastic lecture to start this new class for MIT and all students in mathematics.

  • @salimmiloudi4472
    @salimmiloudi4472 Před 5 lety +4

    Thank you very much Prof. Gilbert Strang, you're awesome as always :))

  • @MichaelKim505
    @MichaelKim505 Před 4 lety +2

    Thank you for the video lectures Prof. Gilbert Strang, I learned a lot from them.

  • @kikirizki4318
    @kikirizki4318 Před 5 lety

    You are amazing mr Strang. Give me deeper understanding about machine learning

  • @ozankaya1061
    @ozankaya1061 Před 3 lety

    I stumbled upon this playlist and it really made my day. This is so good.

  • @avizzzzzzzz
    @avizzzzzzzz Před rokem

    Prof. Strang is a magician. the way he pulls out tricks from his hat and makes sound Linear Algebra concepts fun to students. Respect Respect, only 75% through this video and mesmerized. Charismatic teacher. raw suave, trickery from the magician teacher.

  • @davidorr947
    @davidorr947 Před 4 lety

    Clearly the best teacher on the planet!

  • @kristiantorres1080
    @kristiantorres1080 Před 3 lety

    Thank you MIT for making these lectures public!

  • @zainabedien6674
    @zainabedien6674 Před 5 lety +1

    i HAVE FAST TODAY. I really dont want to do any thing but i started your lecture and just get busy in dimensions. kudos to you Sir. you are my mood changer.

  • @izreeljames7953
    @izreeljames7953 Před 2 lety

    I am grateful for utilizing your gift masterfully ^ beautifully. Thank you Mr. Gilbert Strang!!

  • @jamesgoodman2641
    @jamesgoodman2641 Před 5 lety

    I am convinced that MIT 18.065 is one of the best math courses in the world. There is no exaggeration to say that it serves as the mathematical enlightenment to me thanks Dr Strang

  • @soul2180
    @soul2180 Před 3 lety

    Extraordinary intellect and brilliant math professor

  • @sajalmukhopadhyay9695
    @sajalmukhopadhyay9695 Před 5 lety +2

    You are our inspiration. This is amazing.

  • @vivianhsu7334
    @vivianhsu7334 Před 5 lety +13

    Thank you Dr. Gilbert, you made me fall in love with math,I hope everything is well.❤️🍀

  • @JaGWiREE
    @JaGWiREE Před 5 lety +4

    Thank you so much for releasing this course :).

  • @res0nanc320
    @res0nanc320 Před 5 lety

    So happy to see Professor Strang still teaching beautifully. Even more happy that he’s mentioned Julia already in lecture 1. Thank you MIT for providing such up to date material.

    • @robertcummings952
      @robertcummings952 Před 5 lety

      1q11q11q1qq1q1q1q111q111qqq1111q11q11q1qqq1111111111q11111q1111q11qq111qqq1q111qq11q11q111112q11111q1q1q11q1q1q1q1111111111q1111q111q1q1q1q11q1q111q21111q11111q1qq111q2q1*1212q1221112111q1wwawwweawp

  • @plaustrarius
    @plaustrarius Před 5 lety +2

    This is amazing! Just found out about this and I am so excited!!!

  • @valentinussofa4135
    @valentinussofa4135 Před 2 lety +1

    Maybe I don't have basic in Mathematics, but when I read Prof Strang books about linear algebra (all deep learning for my dream project in machine learning). And now I introduced to Prof Strang OpenCourse, I'm feeling blessed and inspired as Computer Programmer Learner. Thanks to MIT & Prof Strang from East Nusa Tenggara Province, Indonesia. 🙏🙏🙏

  • @hj-core
    @hj-core Před 8 měsíci

    Come from 18.06 tape. Happy to learn from professor strang again🎉

  • @StewieGriffin
    @StewieGriffin Před 4 lety

    A very clear spoken professor.
    I learned a new word. "Bashful" just from the context he used the word in.
    I assumed Bashful meant shy because he asked the students that were bashful to sit far back.
    Which indicates the word "shy" as in the term "camera-shy".

  • @eshwarray3993
    @eshwarray3993 Před 4 lety

    You are the god of Maths.Thank you for making such videos. Most maths teachers know maths but they dont know how to teach maths.You teach in such a way which could be understood by even a high school student.thanks a lot

  • @AdityaSharma-do1ho
    @AdityaSharma-do1ho Před 3 lety

    God bless Dr. Strang!
    There are Innumerable people in the STEM fields who owe their careers to stalwarts like him. A human treasure of knowledge!!

  • @ercanboztepe4468
    @ercanboztepe4468 Před 4 lety

    Thanks legend!!! This course is a key of machine learning area.

  • @pfever
    @pfever Před 5 lety +2

    You have to love MIT! Thank you! :)

  • @arnoldbr8418
    @arnoldbr8418 Před 2 lety

    I love this man, for he, by showing the meaning and relations, makes me love Linear Algebra, a subject that used to bother me.

  • @xy-xe4zl
    @xy-xe4zl Před 5 lety +2

    long time no see, dr.strang! 2year ago i watched linear agebra vedio

  • @flatbreadthom
    @flatbreadthom Před 3 lety +2

    He reminds me of Jimmy Stewart. Very unassuming. Makes out as though he's figuring it out as he goes along, but of course he wrote the book. Zen master at work!

  • @al3xg.0
    @al3xg.0 Před 4 lety

    Professor Strang is an absolute legend!

  • @hankigoe829
    @hankigoe829 Před 2 lety

    it feels great to be getting in on the ground floor of the singularity

  • @magno5157
    @magno5157 Před 5 lety +6

    If there's only one thing to take away from Strang's lectures/lessons, it is this (which he emphasizes in one of his textbooks):
    Understand in depth the four most fundamental subspaces: the row space, the nullspace, the column space, and the left nullspace.

  • @alexkudzin4980
    @alexkudzin4980 Před 4 lety +1

    first row (2 and 1) multiply by 16 ( 32 and 16)
    second row (3 and 1) multiply by -9 (-27 and -9)
    then add the two rows ( 5 and 7)
    (or subtract if you multiplied by 9)

  • @kevintoner6068
    @kevintoner6068 Před 3 lety

    After watching his earlier lectures it feels strang(e) to watch him in such high quality

  • @yuc.w.1217
    @yuc.w.1217 Před 4 lety

    Thank you, Dr. Strang.

  • @jielin6467
    @jielin6467 Před 5 lety +1

    Thank you for the lecture series!

  • @abdulrahmansattar2873
    @abdulrahmansattar2873 Před 5 lety

    Thanks MIT And Prof . Gilbert Strang!

  • @Muxik4k
    @Muxik4k Před 4 lety

    The best professor.. ever!! 😊👍🏼

  • @malyabanbal6738
    @malyabanbal6738 Před 5 lety +1

    great course...was waiting for it for a long time!! :)

  • @Sahil_Love_416
    @Sahil_Love_416 Před 5 lety +1

    Not even a single dislike , that's Gilbert strang for you

  • @jacekc6179
    @jacekc6179 Před rokem +1

    Fantastic weather outside.
    Snow!

  • @grjesus9979
    @grjesus9979 Před 4 lety +1

    That's what I call a good teacher!

  • @iwonakozlowska6134
    @iwonakozlowska6134 Před 3 lety

    24:44 system: 2a+3b=5 , 1a+1b=7 solution: a=16 , b=-9

  • @germantuto6637
    @germantuto6637 Před 4 lety

    Muy buena explicación, que buen curso.

  • @RC-bm9mf
    @RC-bm9mf Před 3 lety +3

    33:52 Professor Strang hasn’t taught the 18.06 for a while and he observes the lectures these days at MIT are taught in a very abstract way, unlike how he presented concepts such a column space 20 years ago. That’s why he said what’s going on? So the ‘range’ terminology of these days is the same as our good friend C(A)!

    • @RC-bm9mf
      @RC-bm9mf Před rokem

      I watched this again! ❤

  • @plekkchand
    @plekkchand Před 2 lety

    Glad the intro properly says "high quality" rather than the illiterate "quality" so often used now to describe the video which follows.. At least there is one place left which respects language. MIT is to be commended for this alone.

  • @alileo1578
    @alileo1578 Před 4 lety +1

    That it is snowing outside makes everything even better :))

  • @nicholasjaramillo9561
    @nicholasjaramillo9561 Před 5 lety +1

    I LOVE THIS GUY!!! AWESOME TEACHER

  • @allandogreat
    @allandogreat Před 4 lety

    It will be such honor to sit there to listen Mr Strang’s lectures

    • @allandogreat
      @allandogreat Před 2 lety

      Come back and study it again, you still can get some new.

  • @MuhammadGhufran5
    @MuhammadGhufran5 Před 5 lety

    Thank u very much Prof. Strang !

  • @vorfour
    @vorfour Před 8 měsíci

    love the snow in background

  • @lianjunmei424
    @lianjunmei424 Před 4 lety

    thank you, professor strang

  • @moueshchronicles
    @moueshchronicles Před 5 lety

    Amazing lecture. Great

  • @henrmota
    @henrmota Před 3 lety

    I would love to have this man as my teacher.

  • @mohammedtarek9544
    @mohammedtarek9544 Před 3 lety

    i have finished 18.06 and i thought that i wont see professor gilbert and the infinite black black board together in a video again
    pretty happy :D

  • @diegoalias2935
    @diegoalias2935 Před rokem

    Thanks a lot for the best math classes

  • @muazahmetsalem5316
    @muazahmetsalem5316 Před 5 lety +8

    you have to respect this man 🙏

  • @ryanwwest
    @ryanwwest Před 3 lety +2

    40:37 "I got excited thinking about math". Best