More Chain Rule (NancyPi)

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  • Опубликовано: 22 окт 2019
  • MIT grad shows how to use the chain rule for EXPONENTIAL, LOG, and ROOT forms and how to use the chain rule with the PRODUCT RULE to find the derivative. To skip ahead: 4) For an example with an EXPONENTIAL function that needs the chain rule to take the derivative, skip to time 0:32. 5) For an example with a natural LOG, skip to 2:34. 6) For an example with a SQUARE ROOT, skip to 4:41. 7) For how to use the CHAIN RULE with the PRODUCT RULE, and how to know which to use first, skip to 7:17. For an introduction of HOW and WHEN to use the chain rule, jump to my FIRST chain rule video: • The Chain Rule... How?... . Nancy formerly of MathBFF explains the steps.
    Support Nancy on Patreon: / nancypi
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    The CHAIN RULE is one of the derivative rules. You need it to take the derivative when you have a function inside a function, or a "composite function". This video picks up at the end of the first chain rule video ("Chain Rule...How? When?" at • The Chain Rule... How?... ) and shows more examples of using the chain rule, as well as how to combine the chain rule with the product rule.
    For an intro of how to take derivatives, jump to: • Derivatives... How? (N...
    4) EXPONENTIAL: for the example y = e^(3x), first take the derivative of the outside function (the exponential function, e). The derivative of the exponential function is just the exponential function itself. When writing the outside derivative, leave the inside function (3x) the same, so write e^(3x). Then by the chain rule, you multiply by the derivative of just the inner function (3x). Since the inside derivative is 3, the answer for the full derivative dy/dx is 3e^(3x).
    5) NATURAL LOG example: To find the derivative of y = ln(5x), use the same steps as above to first take the outside derivative and then multiply by the inside derivative. 5x is inside the natural log. The outer function here is the natural log, ln. To take the derivative of the natural log of something, we write 1 over that something, so 1 over 5x. We leave the inside function alone here when writing the outside derivative, so we write 1/(5x). Remember that we're not done yet. We also need to multiply by the derivative of the inside function. The derivative of 5x is just 5, so our final simplified answer for dy/dx is 1/x.
    6) SQUARE ROOT example: For this example, y = sqrt(x^2 + 1), the x^2 + 1 is under a square root. The square root is the outside, outer function. When you have a root of any kind, before you take the derivative, it's easiest to rewrite it in the form of a fractional power, so that you can use the POWER RULE when taking its derivative. The outside function here is then the 1/2 power, and the inside function is x^2 + 1. To take the derivative of the outside one-half power, we use the power rule to bring down the 1/2 power to the front and reduce the old 1/2 power by 1. We then multiply by the inside derivative, and after simplifying get a derivative of y' = x / sqrt(x^2 + 1).
    Here I used Lagrange notation (y') for the derivative instead of the Liebniz notation from before (dy/dx). To learn the POWER RULE, jump to my video at: • Power Rule... How? (Na...
    7) CHAIN RULE WITH THE PRODUCT RULE: Sometimes you might need to use the chain rule combined with the product rule. How do you know whether to apply the chain rule first, or the product rule first? In this example, y = x^3 (2x - 5)^4, although the second factor here will need the chain rule for its derivative, overall in the biggest view of this function, we have a product of two factors. So we will use the product rule first here on the two factors, and then use the chain rule inside the product rule. However, for an example like ln[x^3 (2x-5)^4)], you would need to apply the chain rule first on the ln form, and then since your inside function is a product, you would need the product rule after that. Basically, the first thing you'll do is whatever you need to use to handle the outermost form of your function.
    For more calculus math help and videos, check out: nancypi.com
    Editor: Miriam Nielsen of zentouro
    / zentouro

Комментарии • 927

  • @tubeonmybulbs
    @tubeonmybulbs 4 года назад +969

    When my grades needed her most, she vanished

    • @ZealousTV
      @ZealousTV 4 года назад +33

      Avatar references>>>

    • @static_sid
      @static_sid 4 года назад +1

      💯

    • @osamaelzayani3788
      @osamaelzayani3788 4 года назад +15

      I follow you because I find your voice so sexy .

    • @ighostx
      @ighostx 4 года назад +1

      😂😂+999999

    • @ZealousTV
      @ZealousTV 4 года назад +25

      @@LeeroyFan101 only the mathertar, master of all four calculuses could stop them, but when the world needed her most, she went offline. 7 months later, my brother and I discovered the new mathertar, Nancy

  • @angelvee5093
    @angelvee5093 4 года назад +324

    You literally helped me graduate so I don’t even take math in college nor do I like math AT ALL but I still watch your videos. You’re an angel!!

    • @paulprice9397
      @paulprice9397 4 года назад +2

      Venus Zambrana Nancypi doesn’t just talk to anyone. You must be someone of advantage to her.

    • @tpstrat14
      @tpstrat14 4 года назад +1

      It sounds like you learned nothing but how to hate part of your brain and you’re thanking her for that. Whoa

    • @angelvee5093
      @angelvee5093 4 года назад +21

      Paul Price 💀💀💀 her videos helped me graduate bro it’s not that deep

    • @angelvee5093
      @angelvee5093 4 года назад +14

      Timothy Stratton I did learn tho, I don’t take math in college cause I did so well in the SAT I didn’t have to take the math courses, you sure do a lot of jumping to conclusions huh?

  • @imsogoingtodie
    @imsogoingtodie 4 года назад +317

    I love the awkward math humor XD

  • @mastrake
    @mastrake 3 года назад +89

    I do like math and love the way you explain. Your reverse-writing technique is very cool and I also enjoy the sound effects.

  • @StayMetal18
    @StayMetal18 4 года назад +20

    I'm currently studying for becoming a math teacher and I just discovered your channel. I love the way you're explaining things ! I hope I'll be able to help understanding as good as what you're doing ! Cheers from France

  • @tdewitt451
    @tdewitt451 4 года назад +260

    Love it!

    • @johubify
      @johubify 4 года назад +36

      Omg, Tyler DeWitt!
      Sir you are the greatest Chemistry and Biology teacher!

    • @kishoresubramani1309
      @kishoresubramani1309 4 года назад +1

      Please do chemical kinetics, electrochemistry videos

    • @farhantanvirfaruque5544
      @farhantanvirfaruque5544 3 года назад +12

      You know a channel is great if Tyler DeWitt acknowledges it

    • @klaviergavin5401
      @klaviergavin5401 3 года назад +6

      Both you and Nancy are my study cramming Gods

    • @janellepello5075
      @janellepello5075 3 года назад +1

      @@klaviergavin5401 same

  • @alexminsky1
    @alexminsky1 4 года назад +282

    Yay, Nancy’s back!

    • @ALLCAPS
      @ALLCAPS 4 года назад +1

      YAY MATH

    • @sxcred275
      @sxcred275 4 года назад +3

      Alex Minsky is she now

    • @Armyboy-wq6rf
      @Armyboy-wq6rf 4 года назад +1

      @@sxcred275 Merely a brief concession, I assure you.

    • @0s0sXD
      @0s0sXD 3 года назад +3

      Boo there she goes again!

    • @Dave.Mustaine.Is.Genius
      @Dave.Mustaine.Is.Genius 3 года назад

      what happened to her back?

  • @TheInfiniteNine
    @TheInfiniteNine 4 года назад +14

    Glad you're back!!😭 thanks so much for making calculus easier to understand! Hope to see you do some higher level calc (2/3) and diff eq videos in the future!

  • @ThinhNguyen-ue1dm
    @ThinhNguyen-ue1dm 4 года назад +49

    Your editing skill is incredible. I would love to see you making videos about matrices and differential equations

  • @jakeschuman4837
    @jakeschuman4837 3 года назад +21

    I’ve been studying for 9 hours and I haven’t understood this until now 😭 thank you so much

  • @NeoDesignCement
    @NeoDesignCement 3 года назад +2

    Why are you so good at explaining math??? I literally haven't seen such good explanations before. YOU ARE LITERALLY AN ANGEL.

  • @blacklightentertainment758
    @blacklightentertainment758 3 года назад +1

    I like how she is calm and subtle about teaching the whole thing.I actually understand the stuff now.So easy.Thanks NAncy!!!!!

  • @robin5on
    @robin5on 4 года назад +8

    Cool, you're back!
    I'm gonna share this new video to my students. Thanks

  • @1cnv
    @1cnv 4 года назад +30

    Welcome back queen of math

  • @gabrielmaghokmathiang5447
    @gabrielmaghokmathiang5447 4 года назад +1

    I understand everything Nancy teaches. She’s one of the best math tutors. Thank you Nancy

  • @thenoob4496
    @thenoob4496 4 года назад +1

    This and the first chain rule video really helped me understand derivatives and helped with integrals. I've been stuck on this for so long. Thank you.

  • @DRMath
    @DRMath 4 года назад +9

    Good job at explaining all at one place. Thanks for sharing the knowledge!!
    Peace ✌️!!

  • @akinpedro5469
    @akinpedro5469 4 года назад +3

    I'm genuinely so happy that she's back

  • @campbellmorrison8540
    @campbellmorrison8540 4 года назад

    I haven't watched any of your posts in the last year but I have to complement you. Your confidence has improved significantly, you were always easy to watch but you are now more loose in your approach. Love it, exactly what I need to pick up where I left off.

  • @valeriapaparo9479
    @valeriapaparo9479 3 года назад

    Literally the clearest and most direct of youtube. Thank you

  • @duncancarterii
    @duncancarterii 4 года назад +3

    NANCY !! Its so great to see you back. I literally have a test tomorrow involving chain rule LOLOL

  • @sarahfox3652
    @sarahfox3652 3 года назад +7

    She is literally my math teacher this semester. All my actual teacher does now that covid started is post links to her videos each week lol she's very helpful tho

  • @shaunt9819
    @shaunt9819 4 года назад +1

    Thanks for the all calculus videos. They really made a big difference for me. Passed cal 1 and finished my associate's degree.

  • @abdullahevazi5196
    @abdullahevazi5196 4 года назад +1

    Welcome back Ms Nancy and Thanks for the great video

  • @nicholaschampagne1976
    @nicholaschampagne1976 4 года назад +5

    Hello Nancy, I feel like I am in college and I have the best Math professor on the planet.
    Your explanation of the equations are soo straight forward, easily understood,
    You need to right a book" math made easy.

  • @Mayacocoice
    @Mayacocoice 4 года назад +46

    youre the only math teacher I actually learn something from, thank you for coming back and saving my grades

    • @tpstrat14
      @tpstrat14 4 года назад

      Grades mean nothing. Math is beautiful. There is not a single comment below thanking her for teaching them beauty of mathematics, because she doesn’t do that

  • @Theoneandonly88able
    @Theoneandonly88able 4 года назад +1

    Keep uploading please I really enjoy these videos to help with math. For those who are looking for an alternative to Nancy during inactivity is professor Leonard and Michel van biezen. They're both equally good in teaching.

  • @swiss4ever93
    @swiss4ever93 4 года назад +1

    Thank you so much!! You can't imagine how much you are helping the students of the world!! 🤗

  • @tybargky3554
    @tybargky3554 4 года назад +6

    Please make more videos :) I’m a engineering student and you help me stay ahead in Calculus 1 w/ analytical geometry

  • @kxmode
    @kxmode 4 года назад +7

    1:22 having the video speedup for "e" by itself. lol ! Also welcome back. :)

  • @djjammindave
    @djjammindave 4 года назад

    Hola Nancy, glad to see you and welcome back. Even though I do not need any more algebra classes it is a pleasure to see you at it, again. Just so you know, I took advantage of your classes in the past, there were very helpful. Thank you.

  • @christinajacobe6151
    @christinajacobe6151 4 года назад

    Calc exam tomorrow and your videos have been a live saver! I swear the last three weeks of lecture haven't even skimmed the surface of what they want us to do

  • @mvrxo
    @mvrxo 4 года назад +10

    Welcome back!

  • @renewd
    @renewd 4 года назад +7

    I got (14x - 15)/[x(2x - 5)] for the last problem. Lots of nice simplification.

  • @chriswhitman8384
    @chriswhitman8384 4 года назад +2

    Hi Nancy! Just wanted to thank you for helping me through my last math class in high school!

  • @gp2580
    @gp2580 4 года назад

    Hey Nancy - great video, and great to see you back!

  • @macyzenier6709
    @macyzenier6709 4 года назад +3

    bless your timing with this video 😂🙌

  • @trumanhicks6404
    @trumanhicks6404 4 года назад +3

    Nancy, where have u been for the past 5 months!? We need u back!

  • @beciz1017
    @beciz1017 Год назад +1

    Studying calculus as part of my engineering course, and your videos help a lot. Thank you!

  • @QwertyWasd17
    @QwertyWasd17 3 года назад

    Nancy...
    I did not comprehend the chain rule at all until watching your videos. 3 weeks into calculus, fresh out of precalc, after watching your videos for precalc... I was dumb to think I could get through calculus without watching your videos lol. Thank you. You're a wizard!

  • @IamFrancoisDillinger
    @IamFrancoisDillinger 4 года назад +25

    Awesome, my Derivatives test is Monday. Perfect timing!

  • @yatindramohan578
    @yatindramohan578 4 года назад +3

    According to me (Maths on youtube)=(NancyPi)..... lots of love from india.... only coz of u i am able to understand my engineering mathematics.....thank u mam

    • @VinodSingh-uy5lt
      @VinodSingh-uy5lt 3 года назад

      This concept in India we studied in 11standard😒

  • @ryanconway779
    @ryanconway779 4 года назад

    You helped me a few times when I was stuck, and reading the problem didn't work, so I am forever grateful for that!

  • @RisteardB2007
    @RisteardB2007 4 года назад +2

    Where have you been? I need your videos. Perfect timing on this one, literally just watched all your others on derivatives last night. Should do videos with loads of examples, would pay for it tbh

  • @JF-bc2lw
    @JF-bc2lw 4 года назад +6

    Wow how did you know I had an exam tomorrow on this lol

  • @alexandergoodwin-elam6996
    @alexandergoodwin-elam6996 3 года назад +51

    I hate how you're objectified for simply existing in a video. Seriously, just wanted to say that I really appreciate these and I hope you keep making more. These have helped me through my senior year of calculus and my seminar physics class and between my cross country practice, student government ECs, and work, I have little to no time to really understand my homework. Thank you so much, have a great day!

    • @weich1q2w
      @weich1q2w Год назад +7

      Okay beta

    • @du4lstrik3
      @du4lstrik3 Год назад +1

      i hAtE hOw yOu'rE oBjeCtifIeD.
      This is the kind of guy that will bow to women and the women will say to him, "Awww you're sooooooo nice!"

  • @user-ob8sq4gy2f
    @user-ob8sq4gy2f 4 года назад +1

    Great! Nancy’s come back! I’m really happy!

  • @madalitsokasongo6132
    @madalitsokasongo6132 4 года назад

    I just love how you explain everything, it's very helpful... Thank you very much Nancy ❤️

  • @om5621
    @om5621 4 года назад +3

    I'd love to see linear algebra, multivariate calculus stuff! 😃

  • @hamids4550
    @hamids4550 4 года назад +18

    Nearly cried when I saw you're back.....jk but seriously glad you're back 😄

  • @rodelioorante8088
    @rodelioorante8088 4 года назад

    thank you for the update. You're the best very clear explanation I also really love you so much welcome back!

  • @SpongebobFan1127
    @SpongebobFan1127 4 года назад +1

    I just subbed yesterday and was surprised to see an upload

  • @anthonycontrera5248
    @anthonycontrera5248 4 года назад +5

    You just saved my ass on a test THANK YOU

  • @Noneblue39
    @Noneblue39 4 года назад +8

    wow i'm too old to remember this. but i do love her ethic

  • @emmanuelmtalis1590
    @emmanuelmtalis1590 2 года назад

    Nancy your channel deserves a millions of likes and subscriptions 100% ❤️❤️❤️

  • @workwithray2569
    @workwithray2569 4 года назад

    Just when my calculus lecturer started talking gibberish, the youtube algorithm delivered to a frustrated me, a piece of NancyPi. Thank you for your work, I can already see an A in this class. (Recently Subbed)

  • @shomiixo
    @shomiixo 4 года назад +3

    shes back

  • @welfareassociationforabdus8533
    @welfareassociationforabdus8533 4 года назад +4

    If she had become my college teacher the student attendence will rise to 200%

  • @cricworld6797
    @cricworld6797 2 года назад

    I was searching for a proper explanation for taking derivatives. Then I accidentally found you. Indeed you deserve more subscribers and more views. You are an angle.Thank you.❤❤

  • @hellostella_
    @hellostella_ 4 года назад

    You're back!!! Your videos helped me through highschool now I'm in college and I still need it😂 thanks Nancy!

  • @letdtrubetol
    @letdtrubetol 4 года назад +15

    She is fire!!!! I love u!!! thanks for getting back at it gorgeous!!!! GO NANCY!!!! #NancyPi

  • @heimerdogger
    @heimerdogger 3 года назад +4

    Didn't know calculus ASMR was a thing...

  • @flymypg
    @flymypg 4 года назад +1

    Wow, this was a birthday present I wasn't expecting. Thanks!

  • @WhyNOTHaveADarkMind
    @WhyNOTHaveADarkMind 4 года назад

    Love your outro but also youre helping me get this HW done during this pandemic.
    I appreciate it

  • @cristian3024
    @cristian3024 4 года назад +6

    I am in love 😍

  • @julianwhippy4470
    @julianwhippy4470 4 года назад +54

    Hey Nancy thanks for helping me understand chain rule now, you're the best and super cute ❤❤❤

    • @bobbob-ks6bg
      @bobbob-ks6bg 3 года назад +4

      Would you feel the need to write super cute on a man's video... ?

  • @mfab1000
    @mfab1000 4 года назад +2

    Omg I literally failed my midterm today because I was lost on the chain rule. You must’ve heard my prayers. Queen.

  • @jailtongs6385
    @jailtongs6385 3 года назад +1

    Great explanation! Thank you, Nancy!

  • @Cheeriot
    @Cheeriot 4 года назад +5

    Beautiful

  • @lalo.g1779
    @lalo.g1779 3 года назад +7

    If someone sees this what happens to the power of 4 in this step: 8x^3(2x-5)^3+3x^2(2x-5)^4, I get how x^2 was a common factor leading to [8x+3(2x-5)] but why Is (2x-5) no longer raised to the power of 4

    • @fly4doe2
      @fly4doe2 2 года назад +1

      I'm with you. Didn't quite get that last simplification. Nor did she refer us to another one of her vids. I guess it is just basic algebra and so we are SOL.

    • @eg8charles
      @eg8charles Год назад +1

      Hi Lalo .g17 and fly4doe, just like x^2 being a common factor so is (2x-5). In fact you could factor up to (2x-5)^3 from both terms. It will leave this..
      y'= x^2(2x-5)^3

    • @PRECIOUSTOMOSORIPELUMI
      @PRECIOUSTOMOSORIPELUMI 7 месяцев назад

      ​@@eg8charlesthanks alot that was helpful❤

  • @kristofferwall8709
    @kristofferwall8709 4 года назад

    Hello and thank you, Nancy. I'm new to derivative and the chain rule so this helped me a lot!
    subbed and looking forward to future videos! Cheers!

  • @Wu.Tang.Financial
    @Wu.Tang.Financial 4 года назад +1

    Your videos really are so helpful, thanks a million 🤙🏼

  • @jorgetasse
    @jorgetasse 4 года назад +6

    2019 still love her

  • @cjeelde
    @cjeelde 4 года назад +13

    You're really one of the best math teachers I've ever seen 😍😍 watched so many of your videos to refresh my knowledge and I have no words for how much I appreciate you 😘😘 I wish I had your channel to watch when I was in school so I could have you as my 2nd teacher. You are THAT amazing!! I truly love you with all of my heart ❤️❤️
    So curious about how your videos are filmed/made when you write 😚😚 is that a top secret or is it possible to reveal that secret someday? 😍
    You are sooooo best!!! ⭐️⭐️⭐️⭐️⭐️ (5/5 stars!) and a bonus: heart with stars -> 💖

  • @user-nl6rd8cb9k
    @user-nl6rd8cb9k 4 года назад

    Great to see you back!!

  • @makkaaz
    @makkaaz 4 года назад

    you deserve more subs for the hard work you put in, keep it up!

  • @goncalofreitas2094
    @goncalofreitas2094 4 года назад +3

    Very nice video! Thanks Nancy!
    Just a quick note about the result in 3:49
    ln(k*x) = ln(k) + ln(x) (property of logs)
    d/dx(ln(kx)) = 0 + 1/x = 1/x (k is a constant)
    When I went through this result I found it very interesting, so thanks a lot for making me more curious!

  • @prometeoalexander7854
    @prometeoalexander7854 4 года назад +15

    I need you in my Life

  • @sgedeon01
    @sgedeon01 4 года назад

    Welcome back Nancy. You’re awesome

  • @temprd
    @temprd 4 года назад

    This timing is impeccable. Literally taking an exam tomorrow.

  • @tedlasso2434
    @tedlasso2434 4 года назад +5

    Welcome Back Babe! 😘😘

  • @stacyyardley261
    @stacyyardley261 4 года назад +6

    Ya still got it, so beautiful. Yes i do mean your wonderful brain.
    Your beautiful to very
    Beautiful.

  • @charlamxnkey
    @charlamxnkey 2 месяца назад

    thank you for your mind and words nancy

  • @rorybrosnan24
    @rorybrosnan24 3 года назад

    Thank you also I appreciate the description box

  • @selinaflowers5981
    @selinaflowers5981 3 года назад +7

    Omg I love how awkward she is. Like same here

  • @nandanshah2813
    @nandanshah2813 4 года назад +10

    Nancy pi is my crush.

  • @ralajmii2241
    @ralajmii2241 4 года назад +1

    My calc test is after 3 hours and u saved my life, ty

  • @raulferri3842
    @raulferri3842 4 года назад +2

    Nancy is very good at it, and I recently followed her videos of Mathematics. I think and I am convinced that a complete video course of "Mathematical Analysis" 1 must start for many interested in this discipline. I hope you follow my simple advice soon Nancy and good work.

  • @nirre4601
    @nirre4601 4 года назад +7

    Is she cute or funny? Im confused 😅

    • @tpstrat14
      @tpstrat14 4 года назад

      Both! And a horrible math teacher!

  • @dontaisnosering9883
    @dontaisnosering9883 4 года назад +6

    I don’t really care about homework. I just wanna see her beauty.

  • @gravity_well5627
    @gravity_well5627 4 года назад

    wow. a gift from god. my math test is today and this video just came out

  • @mduntr7503
    @mduntr7503 4 года назад

    Hit like before the ad even finished playing... NancyPi never lets me down...

  • @slanderalexander2729
    @slanderalexander2729 3 года назад +501

    Goddammit, I'm trying to learn math not fall in love.

  • @karlesmcquade2863
    @karlesmcquade2863 4 года назад +2

    YAY! The internet's best math pedagogue has returned! Welcome back!

    • @djjammindave
      @djjammindave 4 года назад +3

      Pedagogue; A teacher, especially a strict or pedantic one.

    • @karlesmcquade2863
      @karlesmcquade2863 4 года назад +2

      Jeremiah Diaz The word is used as a term of art among teachers to refer to someone who is skilled and experienced in that field. Remember that dictionaries don't always tell you the whole story.

  • @free-energy-systems
    @free-energy-systems 4 года назад

    You make it all seem so simple. If I learn from you then people will think I am smart. That works for me 😊

  • @denisycuna8484
    @denisycuna8484 3 года назад

    Nancy, thank you for existing!

  • @r.w.emersonii3501
    @r.w.emersonii3501 Год назад

    I do like your videos, and wish they were twice as long. Your attitude makes the material appealing.
    Here's an exercise you could use to demonstrate both the chain rule and the product rule: finding the derivative of x**x!

  • @vasundharashinde5847
    @vasundharashinde5847 2 года назад

    Wowww Nancy you are amazing..🤩The way you teach with simplicity is too good

  • @neelpatel3844
    @neelpatel3844 4 года назад

    Glad you’re back!!

  • @jecs3300
    @jecs3300 4 года назад +1

    Welcome back Nancyyyy