Differential equation introduction | First order differential equations | Khan Academy

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  • čas přidán 16. 06. 2024
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    Differential Equations on Khan Academy: Differential equations, separable equations, exact equations, integrating factors, homogeneous equations.
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Komentáře • 475

  • @MrPerry435
    @MrPerry435 Před 2 lety +295

    "I'm assuming you've had a go at it"
    Quite bold of you to assume that Sal

  • @jeffreynorman5221
    @jeffreynorman5221 Před 2 lety +375

    As a student learning differential equation but no textbooks provided in the class, these set of videos means everything

    • @aominetaiga343
      @aominetaiga343 Před rokem +22

      No offense but how in the world can your professor lecture differential equations without providing texts?

    • @josephruvelas9592
      @josephruvelas9592 Před rokem +16

      @@aominetaiga343 probably a school with common exams. math department likely has a curriculum and material to teach/ adhere to but i agree, its kind of unheard of. there probably is a textbook tbh lol

    • @Podzhagitel
      @Podzhagitel Před rokem +2

      z-lib

    • @momouwu1937
      @momouwu1937 Před rokem +2

      @@aominetaiga343 It's kind of normal especially if you are doing an exam specific to a particular developing country and the curriculum isn't the same as the Western countries. You just don't know what textbooks to use. Like if you do SAT exams you know you can use SAT textbooks and if you do A-levels, there are A-level textbooks. Still, if you use other textbooks, it can be helpful.

    • @Meimingming
      @Meimingming Před rokem +2

      @@aominetaiga343 mine just gives us exercises but we have no theory about it😭

  • @matthewlefaivre8975
    @matthewlefaivre8975 Před 4 lety +518

    Sal: So I'm assuming you had a go at it...
    Me: What's a derivative again???

    • @kornelkr6639
      @kornelkr6639 Před 3 lety +6

      😭

    • @epicmatter3512
      @epicmatter3512 Před 2 lety +8

      If you think of a tangent line, which is a line that touches a function at exactly one point, and is really just the limit, both the left side and right side of a secant line, has a rate of change, but is also the rate of change at that exact point. So all your doing is finding the rate of change or more simply rise over run. And these lines are based off of circles, and limits are based off the simple difference quotient, which in itself is just a way to think of rate or change. So all this is, is complex forms of math built off of circles and rate of change(rise over run). And a circle is just based off the idea of a closed loop, and is something people just drew, and rate of change is just the idea about how numbers change over time in a simple linear equation, which is based off of the ideas of numbers and variables, which in itself is based off of the idea of numbers.And a circle is just geometry, which is also based off of numbers. So when you get down to it. ITS ALL JUST NUMBERS! And differential equations are just ways to relate certain functions like derivatives, but actually can relate the world to numbers. ITS ALL JUST NUMBERS!

    • @epicmatter3512
      @epicmatter3512 Před 2 lety +1

      @@kornelkr6639 I got you.

    • @angelfalguera9199
      @angelfalguera9199 Před 2 lety +1

      just exactly what I'm experiencing rn

    • @rendodge7884
      @rendodge7884 Před 3 měsíci

      its also important to understand the anti-derivative

  • @walletinsiders
    @walletinsiders Před 5 lety +1024

    He says "differential equations are super..." My brain is like "EASY??" ^_^ then he says "Useful" -_- Useful stuff is hard bruh

    • @sunitadas8068
      @sunitadas8068 Před 4 lety +5

      Ikr 😂

    • @kinglaserna1533
      @kinglaserna1533 Před 4 lety +17

      Useful? I’ve been learning Calculus since August of 2019 and still have yet to use out side of school

    • @leowu1644
      @leowu1644 Před 4 lety +20

      King La Serna When you get a job in STEM them you will.

    • @cardinality1975
      @cardinality1975 Před 4 lety +18

      @@kinglaserna1533 Surely you've been introduced to some of the applications of calculus? There are a million ways it can be useful, very interesting stuff!!

    • @UltimatePrinceofBB
      @UltimatePrinceofBB Před 4 lety +7

      They are very useful depending on what profession you'd like to take. Calculus is very crucial especially on probability, and there are a lot of professions that requires being good at probability. For example, being an actuary, or having a job at insurance companies

  • @maxarmstrong885
    @maxarmstrong885 Před 7 lety +79

    A great video; I was highly recommended to watch your vids to improve my maths and I have to say you are great at explaining things. I look forward to the whole series of differential equations being this helpful! Many thanks

  • @charleslucas1784
    @charleslucas1784 Před 3 lety +113

    The main thing that I like about the Khan Academy is that he makes advanced math that's usually difficult, a lot easier to understand to where anyone can learn and master what he's teaching.

  • @user-zg4sn5jo6v
    @user-zg4sn5jo6v Před 9 lety +23

    Finally! a new playlist for differential equations, I've been waiting for a year.

  • @gimonoko
    @gimonoko Před 3 lety +43

    When I hear Sal's voice, I automatically listen. I automatically want to learn and understand the lesson. From the years I've spent on khanacademy, he has become my everyday professor/coach when learning. I'm studying electrical engineering right now. Khan academy has its own professor in that department, but when whenever I go back to whatever Sal's teaching, it makes me feel happy to hear his voice.

  • @toby9999
    @toby9999 Před 3 lety +15

    After watching a truck load of introductions to differential equations... finally one that makes sense!

  • @fusion9619
    @fusion9619 Před 3 lety +62

    I'm starting my new years resolution a few months early : watch Khan Academy every day.

  • @MaximQuantum
    @MaximQuantum Před 2 lety +19

    I just figured out a great way to study math at school: Watch videos on the topic to get more insight, intuition and curiousity. This is definitely one of the elements that modern educational systems lack, namely recommending great youtube videos!!!!

  • @zeroseven51
    @zeroseven51 Před 4 lety +16

    Love the way you explain each step
    Easy to understand
    Keep up the good work

  • @jordanmathewbailey
    @jordanmathewbailey Před 6 lety +12

    your videos are by far the most helpful!

  • @angelakate9922
    @angelakate9922 Před 2 lety +4

    I still need to watch this again a couple of times. Because the information just easily flew out of my mind the first time i watched this.

  • @rocketpsyence
    @rocketpsyence Před rokem +6

    This is a good refresher so far. Took diff eq ages ago in college and always felt depressed that it was one of those use it or lose it things and wanted to try and get it back.

  • @akshaypainjane2094
    @akshaypainjane2094 Před 7 lety +61

    You are doing a great stuff by spreading education!
    Hats off!

  • @joshuangtseung6948
    @joshuangtseung6948 Před 3 lety +15

    I used to watch these vids for GCSEs I'm now doing an undergraduate and I'm still here, who says CZcams is a waste of time smh

  • @alassansaine
    @alassansaine Před rokem +1

    This is an amazing introduction to differential equation. I am taking the course this year.

  • @tbpom1003
    @tbpom1003 Před 9 lety +33

    thanks for the video! I'm taking a differential equation class, and my teacher skips all steps. Now I know what's going on lol

    • @jackandonlyjack3268
      @jackandonlyjack3268 Před 6 lety +9

      Teacher skipping steps? I guess it's time to skip your teacher's class.

  • @ignantxxxninja
    @ignantxxxninja Před 3 lety +12

    very nice introduction.. I'm reading the preface of the textbook before the semester starts, and it seems like this is going to make sense.

  • @impooser
    @impooser Před rokem +2

    So simple and straight to the point. Thanks.

  • @zihadhasan7492
    @zihadhasan7492 Před 3 lety

    This discussion is so much live. I mean this discussion has a life to make us understand.

  • @nightt2040
    @nightt2040 Před 3 lety +92

    I’m currently a sophomore in algebra 2. All I wanted to do was take a sneak peek of what math would be like next. The only part I understood was when he showed the algebraic equation 🙃 what is math

    • @katiakominski432
      @katiakominski432 Před 3 lety +31

      Hey, not a bad idea, but you took a bit of a leap here :D You might want to look over (limits and) derivative calculus first, and then you'll understand this a bit.

    • @ThatWasherNerd
      @ThatWasherNerd Před 3 lety +10

      hahaha I have a calc AP test in 6 days and I don't even know what this is.

    • @comprehendnature2404
      @comprehendnature2404 Před 3 lety +12

      In addition to derivatives, you will need integrals and limits to understand differentials. Without them differentials cannot be understood.

    • @alexia8511
      @alexia8511 Před 3 lety +2

      CE student here, and I'm also taking a sneak peek of what's coming.. :'>

    • @datmo0se992
      @datmo0se992 Před 2 lety +7

      WHAT IS MATH?! TEACHER DONT HURT MEEEE DONT HURT MEEE NO MOREEEEE DUN DUNDUN DUNDUN DUH DUH

  • @Jessica_Jessica_Jessica

    This was a great introduction! Thanks!

  • @seanspartan2023
    @seanspartan2023 Před rokem +2

    Thank you for this. I managed to get all the way thru university and get my math degree without taking a single course in Differential Equations. At the time I didn't care because my work only involved theory, but now I regret it because I'm more interested in applied math and physics...

  • @beepnw3659
    @beepnw3659 Před 4 měsíci

    the Grad student that teaches my calc class didn't go over defferentials at all in lecture and then proceeded to put it on the homework. Thank you for saving my grade.

  • @amutuhaireeliza8767
    @amutuhaireeliza8767 Před rokem

    This has been my best introduction to differential equations ever🙏

  • @Mathefusions18
    @Mathefusions18 Před 4 lety

    Straight to the point explanation. Good work..

  • @joshuaaustin2541
    @joshuaaustin2541 Před 4 lety +1

    that silent chain rule you mentioned helped, i laughed 'cause indeed the derivative of e^x is "1" e^x and will repeat in the 2nd derivative. gonna stick around for some more khan videos, prep for college and first at math is differential geometry, this video is just 1% of the entire math146

  • @AlwinEmmanuel-S
    @AlwinEmmanuel-S Před 3 lety

    I rlly love this and i am actually understanding this... even tho im in year 6

  • @mikemustmurder
    @mikemustmurder Před 7 lety +1233

    I'm pretty sure I'm going to fail this class.

  • @theinfeno
    @theinfeno Před 4 měsíci

    I really appreciate that these lectures explain everything in simple words, don't skip any steps, and do not talk down to you like you are stupid.

  • @drmksu38
    @drmksu38 Před 5 lety +2

    thank you Mr kahan .. i cant do anything without your amazing channel ♥️♥️♥️♥️♥️♥️♥️♥️♥️♥️♥️

  • @earllabule4349
    @earllabule4349 Před 3 lety

    looks so hard, but actually so simple....*Mind blown!!!

  • @jaimedelapuente349
    @jaimedelapuente349 Před 4 měsíci

    THis is the BEST video explaining DE, it has finally made me understand them. Thanks a lot :)

  • @kispangit3912
    @kispangit3912 Před 2 lety

    Wow. Finally I know now that the solution of diff.eqs are functions. Gee! Good job! A math mystery finally lifts! Not that I can solve any, haha!!

  • @ikesteroma
    @ikesteroma Před 4 lety +3

    Your handwriting is excellent.

  • @patrickoloo241
    @patrickoloo241 Před 5 lety +1

    that was really useful

  • @clyt9636
    @clyt9636 Před 5 lety

    Thank you!

  • @musicrainbowheals4537
    @musicrainbowheals4537 Před 3 lety +1

    Very clear and simple introduction of "Differential equations" 😊👌

  • @jasdrawssometimes4660
    @jasdrawssometimes4660 Před 6 měsíci

    i wish there was highschool college where you would take college courses on a highschool schedule. so like an hour- 2hours a day, everyday, for a year. i would be so good at differential equations. i wish i had the time to love math the way i did in highschool

  • @johnthegamerman404
    @johnthegamerman404 Před 4 lety +2

    Power series expansion method is my favorite way to solve a differential equation

  • @jamiainaga5853
    @jamiainaga5853 Před 4 lety

    Khan Academy knows everything

  • @sarahrashed7648
    @sarahrashed7648 Před 4 lety

    I got it. thanks!

  • @R4G3QUI7
    @R4G3QUI7 Před 9 lety +1

    very good!

  • @xogmaster
    @xogmaster Před 3 lety +53

    Sal: Here's a differential equation. Figure out if one of the solutions in this list of possible solutions is the solution.
    My professor: Here's a differential equation. Good luck idiot!

  • @JonpritPritam
    @JonpritPritam Před 6 lety

    thnk you very much sir

  • @duckyoutube6318
    @duckyoutube6318 Před 2 měsíci

    Wow this is amazing.

  • @cristianortecioesteban

    Thanks, done watching.

  • @nathaniel4146
    @nathaniel4146 Před 5 lety +49

    Iam about to take this subject next sem! wish me goodluck! just starting to learn... Imma update you guys how I did after this incoming sem. BTW, Im a CE student from Ph. Best of luck also to those engineering students! we can do this!

    • @XDXD15644
      @XDXD15644 Před 5 lety +2

      Best of luck. Im gonna take this subject too. IE student from ph.

    • @itzyryeji3164
      @itzyryeji3164 Před 5 lety

      Bruh i’m grade 12, and planning to take ece, we have De this sem uwuuu from philippines too

    • @snullahc13
      @snullahc13 Před 4 lety

      so, how is the course? I also consider taking DE next semester...

    • @Engr.S-Jay29
      @Engr.S-Jay29 Před 4 lety

      Im an ME student from Philippines. I have my Calculus 1 this semester.

    • @waltercatapang7159
      @waltercatapang7159 Před 4 lety

      Same wd you bruh, God Bless Us

  • @blockbusstar
    @blockbusstar Před 8 lety +169

    This is the second order differential equation

    • @hahaha-zi1xf
      @hahaha-zi1xf Před 4 lety +3

      what is the difference between the first order and second order?

    • @alesolano9081
      @alesolano9081 Před 4 lety +10

      @@hahaha-zi1xf the order corresponds to the bigest derivative in the ecuation (if it has a second derivative then its a second order differential ecuation)

    • @austinpundit6321
      @austinpundit6321 Před 4 lety +7

      Sure, but he was just talking about what a differential equation is.

    • @dxalrado
      @dxalrado Před 4 lety +5

      @@austinpundit6321 look at the title and say that again

    • @toby9999
      @toby9999 Před 3 lety +5

      @@dxalrado He's just talking about differential equations. It's an introduction. We don't care about the order yet. The concept already difficult enough without it.

  • @Bigsneaks818
    @Bigsneaks818 Před rokem

    I’m going to ace this class fr

  • @walktroughman1952
    @walktroughman1952 Před 2 lety +5

    Many people I know hate differential equations, idk I love them to bits, I find them fun. I thought I'd struggle understanding them cause I had struggled with calculus, but it was a surprisingly smooth ride. They really are pretty fun to deal with.
    _Unlike the spawn of Satan that is probabilities and statistics._

  • @thatnibba2551
    @thatnibba2551 Před 5 lety

    This is helpful

  • @thezero4546
    @thezero4546 Před 3 lety

    good job, Thank you

  • @Velas99
    @Velas99 Před měsícem

    Amazing explanation

  • @sujanjirel5456
    @sujanjirel5456 Před 2 lety

    nice video sir..nice explaination

  • @jinoymathew440
    @jinoymathew440 Před 5 lety

    Thank you very much

  • @Jako4460
    @Jako4460 Před 6 lety

    Thanks

  • @theomiado7954
    @theomiado7954 Před rokem

    this is going to be a bumpy ride

  • @jonaskoelker
    @jonaskoelker Před 2 lety +6

    One thing that annoys me about differential equations as they are often presented is that they omit specifying what's a function of what.
    What helps me keep the eye on the ball is this idea:
    When solving a number equation, like x^2 = 4, you're really describing the set { x in R | x^2 = 4 }. One description is to list all the elements: { x in R | x^2 = 4 } = {-2, 2}.
    When solving a differential equation, you're describing a different set, such as the following:
    { f: R -> R | f'(x) = f(x) for all x in the intersection of the domains of f and f' }
    or
    { f: R -> R | f''(x) + 2f'(x) = 3f(x) for all x in the intersection of the domains of f, f' and f'' }
    and so on.
    I have a proof using only ideas from my one-semester real analysis course, without Taylor series, that if f' = f (where f: R -> R) then f(x) = f(0) * e_x where e_x := lim (1+x/n)^n as n -> oo.
    In other words, { f: R -> R | f' = f } is a subset of { f: R -> R | f(x) = f(0) * e_x for all x }. I have only proven that f(x) = f(0) * e_x is a constraint that can be satisfied if f(0) = 0 [implying f(x) = 0 for all x]: I have not proven that non-zero solutions exist, only how they must look _if_ they exist.
    This is a less precise description of the set { f: R -> R | f' = f } than I would like, but it's a start.

  • @jef1ferys
    @jef1ferys Před 7 lety +31

    swear this is second order, not first

  • @zzing9nuna
    @zzing9nuna Před 4 lety

    thanks to make this video

  • @davidfarquharson8207
    @davidfarquharson8207 Před 3 lety

    Thanks bro. 🔥😎

  • @noimosyni_0594
    @noimosyni_0594 Před měsícem

    thank you

  • @TanushAdithiyaBEC
    @TanushAdithiyaBEC Před 2 lety

    Simple and nice

  • @audiomac
    @audiomac Před 7 měsíci

    Thank you. I was so confused when my professor was teaching this because I thought the second derivative was an 11th power lol.

  • @soniakhan4657
    @soniakhan4657 Před 6 lety

    thanks

  • @SilentJnation
    @SilentJnation Před měsícem

    Boom! Mind blown.

  • @vivianmader4523
    @vivianmader4523 Před 3 lety

    hi bestie thanks for the help. love ur handwriting.

  • @jinmingtang1545
    @jinmingtang1545 Před 5 lety +7

    I need to review the chain rule of derivative to understand the calculation.

    • @rokettojanpu4669
      @rokettojanpu4669 Před 4 lety +2

      All it’s about is dealing with derivatives of a composition of functions, i.e. functions wrapped inside other functions.
      If you’ve got a function of x like
      f(g(x)) then the derivative is f’(g(x))*g’(x)
      Example:
      Derivative of (sinx)^2
      = 2(sinx)(cosx)

  • @zevil1999
    @zevil1999 Před 3 lety

    Thank you

  • @sultanwiranatakusumah4154

    Thankyou sir

  • @Aisyah-qf2pz
    @Aisyah-qf2pz Před měsícem

    Thank youuuuuuuuuu.

  • @stvp68
    @stvp68 Před 5 měsíci

    Nicely explained!

  • @cristimarius3940
    @cristimarius3940 Před 5 lety

    neat... thank you!

  • @danielagomez2
    @danielagomez2 Před 9 měsíci

    Thank you so much! My teacher seems to be in a rush all the time and he didn't take the time to explain us what DE's were like you just did. Thank you.

  • @josiahswanson5518
    @josiahswanson5518 Před 2 lety

    There exists a set of an infinite number of solutions to an ODE. Reply with an equation that satisfies the above statement .

  • @uvideos6795
    @uvideos6795 Před rokem

    I have a request.
    Can you arrange the playlist by what order to watch these please?
    Thank you very much.

  • @Healthsolution.694
    @Healthsolution.694 Před 2 lety

    great video

  • @kitchemk
    @kitchemk Před rokem

    Nah I watched a video that just made all of this very intuitive

  • @hikaru3584
    @hikaru3584 Před rokem +1

    here for my midterms, pls pray for me.

  • @davidbosilj
    @davidbosilj Před 2 lety

    may god help us all

  • @nityavyshnavimadduluri3568

    Hello guys ! I guess there's some problem in the audio files for the videos in Khan Academy app.The audio file here is super clear compared to that of the videos in app.

  • @brandonkoh4544
    @brandonkoh4544 Před 5 lety

    Deeper

  • @itsboshd
    @itsboshd Před 9 lety +46

    WHERE DID HE GET e^-3x FROM???????????

    • @semiawesomatic6064
      @semiawesomatic6064 Před 6 lety +3

      srmorales08 I know this is old, but I ran through it with a general e^ax. You end up with a quadratic who's solutions are 1 and negative three. I'm sure there's a more consistent way in another video you've probably already watched, but whatever.

    • @AkashDasYT323
      @AkashDasYT323 Před 6 lety

      from Arab

    • @elenav1210
      @elenav1210 Před 5 lety

      I'm 3 years late but I'm just studying it now.
      He got it from l²+2l-3=0
      Where l² is d²y/dx²
      l is dy/dx and y is just 1
      From there you get -3 and 1 solutions for l.

    • @Gypsy_Danger_TMC
      @Gypsy_Danger_TMC Před 5 lety

      @@elenav1210 Yes just realised you're right. He's used the auxiliary equation

  • @fadhilahrafifpahlevi9166

    Does the y should be exponential to solve differential equations?

  • @wetwillyis_1881
    @wetwillyis_1881 Před rokem +2

    I’d be lying if I said any of this made sense to me.

  • @murtadanor9066
    @murtadanor9066 Před 4 lety

    because the first derivative fo y =x^n dy /dx =nx^n-1

  • @nayangadhvi6986
    @nayangadhvi6986 Před 6 lety

    You can take -3x as x and it will be the same right

  • @hambooger6117
    @hambooger6117 Před rokem +1

    civil engineering student here studying differential equations from scratch! will let you guys know how everything goes for me

  • @Sharna0321
    @Sharna0321 Před 3 lety +7

    Why is your voice oddly so good...

  • @shivangi3030
    @shivangi3030 Před 3 lety

    Why do we eliminate arbitary constants for forming differential equations

  • @rr.studios
    @rr.studios Před 4 lety +9

    Mistook this for ASMR for a bit there.

  • @magilas8485
    @magilas8485 Před 4 měsíci

    Probably one of my hardest class during my second year of engineering. I thought I was pretty good with calculus but this one killed me. Dont know why I was so slow.
    Literally passed this class because of how nonchalant my prof was. Dude was super smart and taught great but dont give af about tests.
    10% midterm
    12% finals
    20% attendance and the rest were just assignments 😂

    • @mykey774
      @mykey774 Před 2 měsíci

      just like me, from the first meeting until now it's almost close to the final exam, I still don't understand this and I'm worried if I don't pass this class lol

  • @nahfid2003
    @nahfid2003 Před 3 lety

    My man Sal. Saved me from a breakdown just now.

  • @abdulrahmanm.bashir4878
    @abdulrahmanm.bashir4878 Před 3 lety +2

    he just said "that is the start"...hmmm i wounder how the end will look like!

  • @alishaiqbal5105
    @alishaiqbal5105 Před 4 lety

    Sir if existance and uniqness fail in ODE than we use numarical method?or we have some other method to solve ODE?

  • @its.the_none
    @its.the_none Před rokem

    Its summer time yet here i am hoping id learn something so i can even have 30% chance of passing. Coz rn my chance of passing is 2.5%. Hopefully, id make it.

  • @_valles3438
    @_valles3438 Před rokem

    so, is the solution typically involved with some form of e^x??