Normal Subgroups and Quotient Groups (aka Factor Groups) - Abstract Algebra

Normal subgroups are a powerful tool for creating factor groups (also called quotient groups). In this video we introduce the concept of a coset, talk about which subgroups are “normal” subgroups, and show when the collection of cosets can be treated as a group of their own. As a motivation, we will begin by discussing congruences.
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We recommend the following textbooks:
Dummit & Foote, Abstract Algebra 3rd Edition
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Teaching​ ​Assistant:​ ​​ ​Liliana​ ​de​ ​Castro
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Пікірлер: 421

  • @Socratica
    @Socratica6 ай бұрын

    If you'd like to learn more, we have a free course on Group Theory! www.socratica.com/courses/group-theory

  • @siddharthprakash8942
    @siddharthprakash89425 жыл бұрын

    The most useful series of mathematics videos I have encountered since 3blue1 brown

  • @randomdude9135

    @randomdude9135

    4 жыл бұрын

    Yup. If you know any other awesome series like this, then it'll help me a lot.

  • @manuthebroker5598

    @manuthebroker5598

    4 жыл бұрын

    I agree

  • @vibodhj349

    @vibodhj349

    4 жыл бұрын

    Check out Faculty of Khan as well.

  • @mychannelofawesome

    @mychannelofawesome

    4 жыл бұрын

    @@randomdude9135 please check Mathdoctorbob's series on abstract algebra... It's really great, really intuitive, and goes into phenomenal depth.

  • @effy1219

    @effy1219

    4 жыл бұрын

    @@mychannelofawesome thanks!

  • @whypeoplehategemini
    @whypeoplehategemini5 жыл бұрын

    I had to play the video multiple times with several pauses along the way for me to grasp the concept.

  • @howmathematicianscreatemat9226
    @howmathematicianscreatemat92264 жыл бұрын

    Everything they do here concerning teaching is badass., meaning they look "bad" in front of most professors because their biggest fear is - paradoxically- to be understood while the greatest mission of Socratica is to appear understandable. And hardly a one does a better job. Because maths is first and foremost supposed to be one thing: intuitive and fun. and ONLY THEN to be formal but only AFTER one has established and examined the concrete cases. Maths then appears to be a collection and characterization of those examples and not a collection of dead and unmotivated formal arguments, definitions and theorems. Formal symbols do have phenomenal value but only if one has gotten and intuitive understanding of the theorems and definitions first. Socratica does exactly this. That's why she should be nominated the Oscar prize for teaching mathematics.

  • @winstonjiang3621

    @winstonjiang3621

    3 жыл бұрын

    “A living Socrates”

  • @howmathematicianscreatemat9226

    @howmathematicianscreatemat9226

    3 жыл бұрын

    Winston Jiang yeah,she kinda is :)

  • @theboombody

    @theboombody

    2 жыл бұрын

    I blame the subject more than the teaching. It's very difficult for me to relate abstract algebra to anything I've seen in the past. The only interest I have for it now is it appears to be central in understanding why there is no general solution in radicals to the quintic equation. Which is interesting, but man, do we have to learn ALL this stuff just to understand that one problem?

  • @alxjones

    @alxjones

    Жыл бұрын

    @@theboombody Linear algebra is abstract algebra, as a vector space is an abelian group with a compatible field action (scalar multiplication). So in a sense, anything you can use linear algebra for is an application of abstract algebra. That aside, the slight generalization of vector spaces (where the field may be weakened to a ring), called modules, appear in calculus on manifolds: the set of vector fields on a (real) manifold M forms a C^r(M,R)-module. A formal theory of polynomials and rational functions also falls under abstract algebra, in the form of rings and fields. Polynomials are more than just "which ones can be solved via explicit formula" though; for example, differential equations such as y'' + 2y' + y = 0 can be studied as polynomial differential operators e.g. D^2 + 2D + 1. This is, of course, trivial for the constant coefficient case, but when the coefficients are polynomials, you end up with a polynomial ring which is not commutative, and so different techniques need to be developed. Groups themselves also find a good amount of importance in calculus and differential equations on manifolds, in the form of Lie groups. Lie groups are groups, first and foremost, which also have some kind of (smooth) manifold structure. Their related objects, the Lie algebras, are vector spaces with a certain kind of vector product (for example, R^3 with cross product is a Lie algebra). It is precisely the properties of groups that make Lie groups so useful, either as a manifold of study or as the typical fiber in a principal bundle structure. One last thing, the quotients that are being developed in this very video are the basis for the major tensor algebras, including the exterior (Grassman) algebra and the symmetric algebra. The tensor product of vector spaces itself is constructed by taking the vector space whose basis is indexed by pairs of vectors, then taking the quotient by the ideal generated by the properties we wish to hold. From the complete tensor algebra, the exterior and symmetric algebras are achieved by taking the quotient by the ideal generated by skew-symmetric and symmetric multiplication, respectively. Ideals are simply the equivalent of normal subgroups for rings and similar contexts, basically those substructures which allow quotients to have the desired structure. This is just a small sample of the use of abstract algebra in other areas of mathematics, obviously localized to my particular area of study. I hope you can come to realize that abstract algebra is not as self-contained as it seems, and the techniques and language learned from studying the subject is of great importance even in the relatively grounded subjects of calculus and differential equations.

  • @itszeen7855

    @itszeen7855

    Жыл бұрын

    @@alxjones what is your area of study/research?

  • @IBMboy
    @IBMboy5 жыл бұрын

    my head hurts :( but i will try to watch it again later :)

  • @randomdude9135

    @randomdude9135

    4 жыл бұрын

    Me too

  • @ScilexGuitar

    @ScilexGuitar

    4 жыл бұрын

    lmao same

  • @randomdude9135

    @randomdude9135

    4 жыл бұрын

    This time I understood atleast 50% I think. Time to ponder on my own and scribble around in a book.

  • @adeelali8417

    @adeelali8417

    4 жыл бұрын

    SAME! I'll come back to the ending later....

  • @ericvosselmans5657
    @ericvosselmans5657 Жыл бұрын

    I am already quite old and trying to learn abstract algebra. Sometimes I just need a very clear and down to earth description of a mathematical object which can be quite hard to teach yourself from a book This channel provides an excellent tool in that regard. Thank you!

  • @ThefamousMrcroissant

    @ThefamousMrcroissant

    Жыл бұрын

    Now try Analysis or Calculus III and absolutely tear those last remaining hairs on your head out. I took a second master in Electrical engineering when I was 32 and I felt like a fucking grandpa already.

  • @samiaario8291

    @samiaario8291

    2 ай бұрын

    I find it helps to have different source material for the same subject, and to skip back and forth between sources. These videos are great for that purpose.

  • @christopherkemsley4758
    @christopherkemsley47583 жыл бұрын

    Somehow I stumbled upon your channel while searching for the Primer Vector Theory a couple days ago, and then watched your entire astronomy series ... and here I am watching the entire Abstract Algebra series. One thing that has always frustrated me trying to learn these things from, say, Wikipedia is that they're always written by people who fully understand the subject FOR people who fully understand the subject and and are quite difficult to understand until you understand it - even in cases where the concepts are quite simple. I'm so glad to have found your channel where you explain things so simply and so clearly. Thank you so much!

  • @yeast4529
    @yeast4529 Жыл бұрын

    You know it's a good video when the content seems simple and is really easy to comprehend. Sometimes I lose myself in all of the new definitions etc. in my Algebra course, but these videos pull everything together and help greatly with the motivation behind everything you learn.

  • @alexamadori9884
    @alexamadori98844 жыл бұрын

    Can watch this almost effortlessly in the evening, trying to read the same theory from a book took almost a week of studying every morning and led to a more superficial understanding than this video. You guys are geniuses when it comes to presenting ideas, you're definitely on the list of channels I'd like to support when I'll be able to.

  • @homiramanuj

    @homiramanuj

    11 ай бұрын

    In Motivating Example, How do we get remainder 1 if we divide -14, -9, -4 etc. by 5? Please reply i am so confused 😢 integer mod 5 is confusing me

  • @godspower_eze

    @godspower_eze

    10 ай бұрын

    @@homiramanuj The smallest number closest to -4 that is divisible by 5 is -5 so -4 - (-5) is 1. Same goes for -9, -14 and so on.

  • @erfanmirzaei705

    @erfanmirzaei705

    8 ай бұрын

    @@homiramanuj In the division quotient can be negative numbers. Thus, by dividing -14 by 5 we get -3 as quotient and -14-(-15)= 1. The point here that the quotient times divisor should be less than or equal to dividend.

  • @Arv.-
    @Arv.-5 ай бұрын

    The way you simplify a complex concept is great!

  • @sadied0g
    @sadied0g5 жыл бұрын

    This playlist is awesome! TOPOLOGY WHEN?!?!? 😁👍🏻

  • @bakkamydestination

    @bakkamydestination

    2 жыл бұрын

    S... waiting

  • @souravacharya
    @souravacharya5 жыл бұрын

    The way she teaches and explains , totally incredible...!

  • @ozzyfromspace
    @ozzyfromspace4 жыл бұрын

    This was my first time trying to learn and it didn't help. But I'm gonna try again, and again, and again until it makes sense. I'm committed to finishing your playlist with usable understanding. Keep up the amazing work, Socratica team!

  • @luyombojonathan7715

    @luyombojonathan7715

    2 жыл бұрын

    How did it go ??? Am starting on a similar journey

  • @ThePimp4dawin
    @ThePimp4dawin4 жыл бұрын

    What an amazing series, this is a goldmine! Perfect depth and speed.

  • @alayamaryim
    @alayamaryim2 жыл бұрын

    The most understandable videos of abstract algebra on KZread.Very easy to understand

  • @homiramanuj

    @homiramanuj

    11 ай бұрын

    In Motivating Example, How do we get remainder 1 if we divide -14, -9, -4 etc. by 5? Please reply i am so confused 😢 integer mod 5 is confusing me

  • @ClumpypooCP

    @ClumpypooCP

    7 ай бұрын

    @@homiramanujbecause -4 = (-1)*5+1

  • @jonathanpopham5483
    @jonathanpopham54834 жыл бұрын

    the most approachable abstract algebra course online. thank you so much for your hard work!

  • @joshuaronisjr
    @joshuaronisjr4 жыл бұрын

    From 6:00 onwards, although the real case is more general, the entire thing becomes a lot easier to understand if every time she says "times" or "multiply" you think "plus" or "add", every time she says "N" you replace it with "Modulo(someNumber)", "e" is "0Modulo(someNumber)", and "x" and "y" are just numbers that aren't a multiple of someNumber. Cheers!

  • @merlijn1e
    @merlijn1e2 жыл бұрын

    I use this series to accompany my lectures on abstract algebra, it helps me so much to understand what is going on. Thankyou!

  • @Anna-jy7cj
    @Anna-jy7cj4 жыл бұрын

    This series is blowing my mind, your work is highly appreciated

  • @homiramanuj

    @homiramanuj

    11 ай бұрын

    In Motivating Example, How do we get remainder 1 if we divide -14, -9, -4 etc. by 5? Please reply i am so confused 😢 integer mod 5 is confusing me

  • @tekhiun
    @tekhiun4 жыл бұрын

    One of the best math series on youtube. maybe the best if you already have enough background to understand this. Thank you for doing this !

  • @Socratica
    @Socratica2 жыл бұрын

    Sign up to our email list to be notified when we release more Abstract Algebra content: snu.socratica.com/abstract-algebra

  • @tomjoyce9401
    @tomjoyce94012 жыл бұрын

    Excellent presentation: clear, to-the-point, fluid.

  • @raunitsingh676
    @raunitsingh6763 жыл бұрын

    Trying to find a word that describes my gratefulness for such incredible explanative videos.

  • @malenaalmasi1774
    @malenaalmasi17744 жыл бұрын

    In really like the presentation style. Everything is very clear and all the explanations are easy to follow. Thank you so much

  • @Bloodsaberxy
    @Bloodsaberxy4 жыл бұрын

    Was self studying Galois Theory and this helped to recap a lot of forgotten theorems, thanks a lot!

  • @user-gc4dx4nt2x
    @user-gc4dx4nt2x4 жыл бұрын

    she saved my whole fxxking life during the senior this fall

  • @cameronspalding9792
    @cameronspalding97923 жыл бұрын

    @11:04 the set of permutations (123) (132) and the identity permutation form a normal subgroup of S3

  • @Yougottacryforthis

    @Yougottacryforthis

    Жыл бұрын

    isnt it the only (non trivial) sub group as well as the only normal sub-group? any other basically fail to endure the closure property

  • @cameronspalding9792

    @cameronspalding9792

    Жыл бұрын

    @@Yougottacryforthis it’s the only non trivial normal subgroup, but not the only non trivial subgroup, just pick a set containing the identity and a 2 cycle

  • @Gaspard832011
    @Gaspard8320114 жыл бұрын

    Group is [ i (identity) , r1 (rotation 1/3), r2 (rotation 2/3), s1 (sym 1), s2 (sym 2) , s3 (sym3) ] (i,r1,r2) is a subgroup. This subgroup is normal because: s1* r1 *s1 =r2 s2* r1 *s2 =r2 s3* r1 *s3 =r2 (a symetry is its own inverse element)

  • @sammie1824

    @sammie1824

    Жыл бұрын

    I got this too!

  • @homiramanuj

    @homiramanuj

    11 ай бұрын

    In Motivating Example, How do we get remainder 1 if we divide -14, -9, -4 etc. by 5? Please reply i am so confused 😢 integer mod 5 is confusing me

  • @AdamDaouk-mb7ly

    @AdamDaouk-mb7ly

    7 ай бұрын

    eh meshe

  • @GGC728
    @GGC728 Жыл бұрын

    The best video i ever viewed on youtube about group theory. Thanks alot

  • @Souley239
    @Souley2395 жыл бұрын

    I really like you because explain the subject in an easy and understandable way.

  • @sujoydey8359
    @sujoydey83594 жыл бұрын

    Too good explanation which covers most important part of normal subgroup. U are truly a good teacher.

  • @saeedahmedhashmi9448
    @saeedahmedhashmi94483 жыл бұрын

    Mam your way of delivering lecturer is amazing,outstanding.. God bless you

  • @cameronspalding9792
    @cameronspalding97922 жыл бұрын

    @7:25 replace y with y^(-1)

  • @192ali1
    @192ali14 жыл бұрын

    Thank you. Excellent presentation.

  • @carlsagan9808
    @carlsagan98087 ай бұрын

    These videos are so helpful it's unreal

  • @ThePharphis
    @ThePharphis5 жыл бұрын

    Damn I really needed this video 4 days ago before my exam! (it went ok but factor groups was something that went over my head for most of the semester)

  • @pubudunuwan1751
    @pubudunuwan17512 жыл бұрын

    your all videos are very descriptive .it helps to solve many troubles .i wish to do more and more videos. thank you

  • @quahntasy
    @quahntasy5 жыл бұрын

    This was explained very amazingly. Thanks for this :)

  • @Socratica
    @Socratica2 жыл бұрын

    Socratica Friends, we wrote a book for you! How To Be a Great Student ebook: amzn.to/2Lh3XSP Paperback: amzn.to/3t5jeH3 or read for free when you sign up for Kindle Unlimited: amzn.to/3atr8TJ

  • @murielfang755
    @murielfang7552 жыл бұрын

    So so great. So well delivered.

  • @ajsdoa6282
    @ajsdoa62825 жыл бұрын

    Thanks! Had to watch in 0.5x the speed to hang on, but very helpful! :)

  • @physicslover9227
    @physicslover92273 жыл бұрын

    Thanks a lot this videos series is very useful. It explains everything in a very simple way🙂🙏🏻🙏🏻.

  • @maulikjain3894
    @maulikjain38942 жыл бұрын

    one can listen this forever/..

  • @ashmytom8927
    @ashmytom892710 күн бұрын

    You have made things simple!....Thankyou

  • @syamalchattopadhyay2893
    @syamalchattopadhyay28933 жыл бұрын

    Outstanding video lecture. This video lecture is very helpful for self-study.

  • @souravsingh3025
    @souravsingh30255 жыл бұрын

    Great explaination love it , makes the topic fun 💝💝

  • @SpiritVector
    @SpiritVector4 жыл бұрын

    Simple groups are the primes of group theory.

  • @ijyoyo
    @ijyoyo2 жыл бұрын

    WOW, so nice and easier to understand. Beats the textbook 100%.

  • @youtwothirtyfive
    @youtwothirtyfive Жыл бұрын

    One more bit of constructive feedback, the exercise at the end, "find a normal subgroup of S_3", assumes knowledge of what symmetric subgroup S_3 is --going by the Abstract Algebra playlist order, the concept of a symmetric subgroup hasn't been introduced yet.

  • @exx8eran
    @exx8eran3 жыл бұрын

    wow you took such a complicated subject and make it so simple.

  • @sutanuhait3283
    @sutanuhait32832 жыл бұрын

    Excellent work. Students are recommended to watch this video. It will help to motivate you properly.

  • @ajaykanwar7223
    @ajaykanwar72235 жыл бұрын

    *Love the way you teach*

  • @KeystoneScience
    @KeystoneScience5 жыл бұрын

    just in time for finals ;)

  • @Socratica

    @Socratica

    5 жыл бұрын

    Hooray! That's what we were hoping. :D Good luck!!

  • @CreolLanguag

    @CreolLanguag

    4 жыл бұрын

    @@Socratica i have a question: since y^-1(N)y = N, if we multiply both sides by y in their left. y[y^-1(N)y] = yN Ny = yN so does this mean that cosets form a group only if left cosets is the same as their right cosets? is this always the case?

  • @haroonahmad1850

    @haroonahmad1850

    4 жыл бұрын

    @@CreolLanguag good question. What's the answer of this question? Did you get it?

  • @jamaluddin9158

    @jamaluddin9158

    3 жыл бұрын

    @@CreolLanguag Yes that is correct!

  • @rekarlopunzalan

    @rekarlopunzalan

    3 жыл бұрын

    Watching this during finals

  • @LuizaDreamsDeutsch
    @LuizaDreamsDeutsch2 жыл бұрын

    Thank you so much for the explanation!

  • @LOL091027
    @LOL0910275 жыл бұрын

    When we will have topology series like abstract algebra ?

  • @DiegoGonzalez-xl9us

    @DiegoGonzalez-xl9us

    4 жыл бұрын

    i wish they do it

  • @howmathematicianscreatemat9226

    @howmathematicianscreatemat9226

    4 жыл бұрын

    Would you want me to ? Or in other words: would it still be useful for you ?

  • @_qpdbdbqp_

    @_qpdbdbqp_

    4 жыл бұрын

    @@howmathematicianscreatemat9226 yes!!

  • @howmathematicianscreatemat9226

    @howmathematicianscreatemat9226

    4 жыл бұрын

    @@_qpdbdbqp_ okay, till when do you still need it? Tell me the date and also if you think good explanations could help your classmates too? If you tell me, then maybe I'm gonna start producing them when I'm back from holiday on the 25th of February. You would then view your first plesant set-topology video on the 27th of February. But if you want to me to start, confirm your request.

  • @John-js2uj

    @John-js2uj

    4 жыл бұрын

    @@howmathematicianscreatemat9226 I'd also be grateful if you began posting on 27th Feb

  • @njahnavi7943
    @njahnavi79433 жыл бұрын

    Thanks a ton !!! Explained with such clarity. It was to the point , excellent explanation.❤️

  • @sudarshann7194

    @sudarshann7194

    Жыл бұрын

    Is it nityananda who's in your profile?? 🤔

  • @AdamDaouk-mb7ly

    @AdamDaouk-mb7ly

    7 ай бұрын

    @@sudarshann7194 eh ktir excellent

  • @rosakuli8375
    @rosakuli83752 жыл бұрын

    studying for my math classes is enjoyable with Socratica

  • @sarthakkrishna1737
    @sarthakkrishna17373 жыл бұрын

    So well explained!!!! Thank you! I have an exam tomorrow. I have now more confidence than apprehension XD

  • @fuckthishandlesystem
    @fuckthishandlesystem4 жыл бұрын

    THANK YOU SO MUCH FOR THIS

  • @kunslipper
    @kunslipper5 жыл бұрын

    Very good. Thank you so much.

  • @moularaoul643
    @moularaoul6433 жыл бұрын

    Thank you so much!!!

  • @RobotProctor
    @RobotProctor4 жыл бұрын

    I wish I could upvote this video 100 times.

  • @gauravsahu2495
    @gauravsahu24954 жыл бұрын

    I love the way you teach

  • @ishikasharma1000
    @ishikasharma10003 жыл бұрын

    This is so helpful, I can now clearly visualise these concepts 😍🙌. Your videos are amazing, Thankyou Socratica✨

  • @mohammadamanalimyzada8332
    @mohammadamanalimyzada83323 жыл бұрын

    thank u i love the way u teach. I didnt understand my professor but here go everything I needed any videos on Mathematical Analysis?

  • @keshabsingha7111
    @keshabsingha71114 жыл бұрын

    it's very helpful to me . thank you .

  • @shockline1
    @shockline14 жыл бұрын

    Very helpful videos. I had to pause a lot to understand but worth it.

  • @amberszulc197
    @amberszulc197 Жыл бұрын

    that was..... amazing. great job

  • @jeromejean-charles6163
    @jeromejean-charles61634 жыл бұрын

    Very good work : still to give a constructive critic: 1) I think the argument for definition yN=Ny could be exposed without going down to elements and avoiding inverse as much as possible.2) The transition from Z,+ to multiplicative is not the best though I cannot think of a simple multiplicative example fro cosets.3) It is so nice to finally see questions being asked to motivate a definition. Still from a didactic point of view it could be worth repeating the question at end ( recap style).

  • @EdgarMartinez-ws9ws
    @EdgarMartinez-ws9ws4 жыл бұрын

    Such a beautiful topic

  • @narendrakhadka9598
    @narendrakhadka9598 Жыл бұрын

    You are my best teacher.

  • @rakoonberry7879
    @rakoonberry78795 жыл бұрын

    You people are amazing!

  • @ramumaha2779
    @ramumaha27793 жыл бұрын

    took me watching it twice to understand perfectly(have to oil my brain)....awesome to the point explanation.

  • @Socratica

    @Socratica

    3 жыл бұрын

    This is our favourite thing about KZread compared to classes - you can just rewatch! Thanks for sticking it out with us! 💜🦉

  • @halilibrahimcetin9448
    @halilibrahimcetin94483 жыл бұрын

    Happiness is nothing but understanding stg properly. These vids series are fuckin' awesome.

  • @ramzihedimay1179
    @ramzihedimay11792 жыл бұрын

    great and very well done. Congratulation.

  • @benjiasdf
    @benjiasdf5 жыл бұрын

    great video, thanks a lot!

  • @shipratiwari1533
    @shipratiwari15334 жыл бұрын

    Very interesting explanation...!!!!

  • @germanslobo
    @germanslobo4 жыл бұрын

    Thanks. Great video. !!

  • @theboy4773
    @theboy47735 жыл бұрын

    saving my time & leisure time

  • @simasimo9796
    @simasimo97965 жыл бұрын

    Need to watch More videos 😃

  • @trainingvlogs
    @trainingvlogs3 жыл бұрын

    Pls make more videos on abstract algebra i love your explanation very much

  • @turokg1578
    @turokg1578 Жыл бұрын

    bro this video is amazing. i was like wtf is this quotient groups and cosets reading dummit&foote. came here and its all clear now. can continue reading. thanks

  • @SuperAwesomeReasons
    @SuperAwesomeReasons5 жыл бұрын

    Yes! More Socratica.

  • @ubersham
    @ubersham2 жыл бұрын

    Where were you in 2016 when I was taking Abstract Algebra??? 😝 Love the series. I’ll be going through each one several times until I understand your proofs and can duplicate them (again?).

  • @profsciencia
    @profsciencia2 жыл бұрын

    these videos are awesome!

  • @malicksoumare370
    @malicksoumare3705 жыл бұрын

    My favourite teacher

  • @shacharh5470
    @shacharh54705 жыл бұрын

    S(3) is isomorphic to D(3) the dihedral group of 6 elements so the normal subgroup would be the rotations or the subgroup generated by a 3-cycle.

  • @Nand0san35

    @Nand0san35

    3 жыл бұрын

    Yes, I agree, and it is easy if you see that all inverses out of rotation subgroup are itself. f1*g1*f1=g1

  • @ronycb7168
    @ronycb7168 Жыл бұрын

    Indian here really enjoying this series happy republic day guys

  • @homiramanuj

    @homiramanuj

    11 ай бұрын

    In Motivating Example, How do we get remainder 1 if we divide -14, -9, -4 etc. by 5? Please reply i am so confused 😢 integer mod 5 is confusing me

  • @youtwothirtyfive
    @youtwothirtyfive Жыл бұрын

    Wow, great video! I learned a lot. One thing that felt unexplained was this statement just before 10:00 about factor groups that "the inverse of x⋅N is x^(-1)⋅N". I can play around with the integers mod 5 as an example and see it's true, but I'm wondering how to convince myself it works in general. Thanks again for making these :)

  • @vladislavnikolaev800

    @vladislavnikolaev800

    Жыл бұрын

    N is invariant subgroup, it means that for any x xN=Nx. (xN)(x^(-1)N)=(Nx)(x^(-1)N)=N(xx^(-1))N=N1N=NN=N. In factor group N is 1.

  • @s.k.potdarpotdar8377
    @s.k.potdarpotdar83774 жыл бұрын

    bye socratica, i watched your video on normal subgroups& quotient groups. very beautiful presentation & interesting maths subject. it is my request tu pl relaese vedio on "boolean algebra & it's applications" thank u

  • @aashishkumarmaurya55
    @aashishkumarmaurya555 жыл бұрын

    Thanks again

  • @finn5571
    @finn55714 жыл бұрын

    So how would one prove the second part of the statement at 7:27? I proved it by showing the first part, and then showing that the two have to have the same order and no duplicates. I'm not sure if this is the right approach though.

  • @hemanthkumartirupati
    @hemanthkumartirupati5 жыл бұрын

    Do you plan to teach vector spaces in future? Your videos are incredibly helpful btw :) Thanks a lot

  • @ooos2989

    @ooos2989

    4 жыл бұрын

    They have a video on it from three years ago.

  • @renatoalencar4451
    @renatoalencar44512 жыл бұрын

    That's great! I bet you can do one on type theory.

  • @abelabel4151
    @abelabel41513 жыл бұрын

    thank you. from marrakech morocco

  • @truthteller3978
    @truthteller39785 жыл бұрын

    A video on isomorphism theorems please

  • @cameronspalding9792
    @cameronspalding97923 жыл бұрын

    @11:03 the set {I, (123), (132)} is a subgroup of S3

  • @Mathematics-with-MohsinRaja
    @Mathematics-with-MohsinRaja Жыл бұрын

    Amazing

  • @cameronspalding9792
    @cameronspalding97922 жыл бұрын

    @10:45 if you find the factors associated with the composition series: is it possible to then reconstruct the group after factoring it

  • @ibrahimhamim3135
    @ibrahimhamim31354 жыл бұрын

    Salute to you guys 👌