Area & Arc Length of a Cycloid (one arch)

Sdílet
Vložit
  • čas přidán 13. 09. 2024
  • Check out this video for 100 integrals so you won't forget your integrals again! • 100 integrals (world r...
    Which one did you like more?
    Area of a cycloid, 1:00
    Arc Length of a Cycloid, 8:45
    Parametric Equations Overview: • Parametric Vs. Cartesian
    For more resource, please visit: www.blackpenre...
    Click to subscribe for more math contents: www.youtube.co...
    Check out my T-shirts & Hoodies: teespring.com/...
    support bprp on Patreon (there's a discount code to bprp Teespring store for everyone) / blackpenredpen
    I create my site www.blackpenred.com on Wix, give it a try: wixstats.com/?a...
    Check out my site & social media
    😃 blackpenredpen...
    😃 / blackpenredpen
    😃 / blackpenredpen
    Thank you for your support!
    blackpenredpen | 曹老師

Komentáře • 148

  • @letsseepaulallenscard.6604
    @letsseepaulallenscard.6604 Před 5 lety +30

    Comfy bprp maths after a long day of work is best maths

  • @Cosine_Wave
    @Cosine_Wave Před 5 lety +18

    0:45 The arc length and area can be calculated by using y = 2r(arccos(x/r) + sqrt(1-(x/r)^2)) and integrating between -r and r. It's not exactly what you asked for, but it will give the correct answer. The difference is that the circle is rolling on the y axis instead of the x (along with a few simplifications to the equation). I also don't know how hard that is to integrate.

  • @XZellTheBest
    @XZellTheBest Před 5 lety +13

    I prefer the first integral. I'm not a math student, I'm just an agronomist, but I love your videos. Please keep going! Greetings from Italy!

  • @JonahFoley
    @JonahFoley Před 5 lety +73

    10:44 the true fans watch the whole video :)

  • @GreenMeansGOF
    @GreenMeansGOF Před 5 lety +48

    Darn. No π in the arc length.

  • @sander_bouwhuis
    @sander_bouwhuis Před 3 lety +2

    I love your enthusiasm! Thanks for working this out very clearly.

  • @rollinginthedeep6900
    @rollinginthedeep6900 Před 4 měsíci

    10:43 hahah, thank you for being an awesome tutor. I like watching your explanations because they're clear and you remind me that math should be fun! It's hard to remember to enjoy learning when exam season comes around, so thank you for all your videos and your help :)

  • @benjaminbrady2385
    @benjaminbrady2385 Před 5 lety +5

    10:43 love you bprp

  • @StuartSimon
    @StuartSimon Před 2 lety +3

    The cycloid passes the vertical line test, so it is actually theoretically the graph of some function f. I was thinking that you could come up with a closed form of f(x) for the first arch by defining a function g on the interval [0, 2pi). Then you could define f as f(x) = g(x mod 2pi).

  • @dsantistevan99
    @dsantistevan99 Před 5 lety +1

    I remember doing this and the rotation volume of a cycloid for high school, so cool. Nice vid

  • @Linuxmusica
    @Linuxmusica Před 5 lety +4

    The area is 3 times the area of the circumference with r radius.

  • @User84367
    @User84367 Před měsícem

    this question was in my book so awesome

  • @frozenmoon998
    @frozenmoon998 Před 5 lety +2

    1+1 = 2 - you've got to say it with *authority*. I never have been told before in my life with such enthusiasm that 1+1 = 2.

  • @MrJapogm
    @MrJapogm Před rokem

    10:43 Watching the whole video. Awesome curve. Mind-blowing properties.

  • @carissagamboa9412
    @carissagamboa9412 Před 2 lety

    Why do you make this sound so exciting ! Lol I am having a hard time, but your videos are so encouraging! Thank you!!

  • @EpochIsEpic
    @EpochIsEpic Před 5 lety +2

    Well, this went WAY over my head but still interesting to watch 😂

  • @yurusan721
    @yurusan721 Před 5 lety +1

    Although I didn't take calculus in high school, I still like your videos.
    They are so satisfying to watch. 10:45

  • @bachirblackers7299
    @bachirblackers7299 Před 3 lety

    Crazy result of 8r !!! Thanks

  • @Vishnu-jr3wv
    @Vishnu-jr3wv Před 11 měsíci

    Oh thanku
    I have a presentation about cycliod,u help me alot❤

  • @drpeyam
    @drpeyam Před 5 lety +6

    Your right hand on the thumbnail looks like a zot zot zot symbol 😄

    • @blackpenredpen
      @blackpenredpen  Před 5 lety +4

      Dr Peyam
      It’s the right hand and the left hand rules!!!

    • @drpeyam
      @drpeyam Před 5 lety

      Hahaha, makes sense!!! Zot zot zot!

  • @EpochIsEpic
    @EpochIsEpic Před 5 lety +7

    10:44 Still watching. I’m gunna have to stop so I still have time to do my precalc HW. Looking forward to tomorrow’s video though!

  • @saw09200
    @saw09200 Před 5 lety +1

    At first glance the integral for the arc length looked more difficult. The area integral was simple if you knew the identity. Then again you make everything look easy hahaha

  • @igorjasenovski4313
    @igorjasenovski4313 Před rokem

    Pretty good video. Thank you for your beautiful job. Keep it up.

  • @Shahd_jul119
    @Shahd_jul119 Před 3 lety

    my savior thankk you

  • @ajitfhamacademy
    @ajitfhamacademy Před 5 lety +1

    can you give me the name of a book who content like these problems , thanks , i love your videos i watch you every day

  • @peterchan6082
    @peterchan6082 Před 5 lety

    First thing first . . . There was no mention whatsoever on HOW the parametric equation of the cycloid was derived.
    And by the way there indeed IS a Cartesian way of writing the equation (without using parameters).
    Thus the equation of the cycloid as the locus of a point on the circumference of a circle radius r rolling on the x-axis, beginning from the origin, is given by . . .
    x = arccos(1 - y/r)) - sqrt[y(2r - y)]

  • @olanmills64
    @olanmills64 Před 4 lety +4

    Wow, I would have predicted the arc length formula to include π.

  • @twiceaesthetic
    @twiceaesthetic Před 3 lety

    Can you use disk method here?

  • @nunyabiznasspunk
    @nunyabiznasspunk Před 4 lety

    10:46. True fan

  • @carolinewernowski2530
    @carolinewernowski2530 Před 4 lety

    Just checked - 1+1 IS 2!
    Respect your AUTHORITAY!
    13:05

  • @crazypyrokitty
    @crazypyrokitty Před 4 lety

    Your problem works out to be almost the same as my homework problem (just without a constant "r") and I'm stuck on the (2-2cost) in the sq.rt so I'm hoping you're about to show me how to make it easy lol

  • @hydropage2855
    @hydropage2855 Před 2 lety +1

    10:42, I'm still watching! I think this step will be a little harder

  • @Josh-et2zv
    @Josh-et2zv Před 5 lety +2

    Very cool, but can you do the integral of x^(dx)+1 ?

    • @blackpenredpen
      @blackpenredpen  Před 5 lety +1

      Yea, Dr. Peyam did a video on that already: czcams.com/video/shdK9DAiDBE/video.html

  • @locolaz1182
    @locolaz1182 Před 4 lety

    In these times of coronavirus you have officially become my tutor/professor 🤣

  • @peterchan6082
    @peterchan6082 Před 5 lety

    Cartesian equation of the cycloid
    x = r arccos(1 - y/r) - √[y(2r - y)]

  • @JordHaj
    @JordHaj Před 5 lety

    10:44 watching from the very start as always!

  • @PriyankaJain-wd7ks
    @PriyankaJain-wd7ks Před 5 lety +1

    GREAT WORK....

  • @TrimutiusToo
    @TrimutiusToo Před 5 lety +2

    Old time friend 1+1=2 need to say with authority!

    • @sander_bouwhuis
      @sander_bouwhuis Před 3 lety

      Ha ha ha, he did the same thing with the '2 * -2 = 4' at 18:44. I guess he likes his constants.

  • @MichaelaFlowers
    @MichaelaFlowers Před rokem

    Yes I love the confidence! You really helped a lot! Also the jokes

  • @egillandersson1780
    @egillandersson1780 Před 5 lety +1

    It does not matter here since, for t going from 0 to 2pi, t/2 is going from 0 to pi and so sin(t/2) is always positive. But in a general case, when you put the sin square out of the square root, don't you have to take the absolute value ? (sorry for my bad english)

  • @cameronspalding9792
    @cameronspalding9792 Před 5 lety +1

    Sin^2(t)=(1-cos(2t))/2

  • @akshinbarathi8914
    @akshinbarathi8914 Před 3 lety

    high standart content given by red pen black pen. very impressive sir. i found it usefull for my deriviations. CAN U ALSO PUT A VIDEO ON BRACHISTOCHRONES? ( a big fan from india) well one doubt how were u able to use two pen in one hand? ur amazing sir!!!!!!!!!!!!!!!!!!!!

  • @ajitfhamacademy
    @ajitfhamacademy Před 5 lety

    thank you

  • @procerpat9223
    @procerpat9223 Před 3 lety

    you need to explain how you got the area formula

  • @putthipongnamwol7061
    @putthipongnamwol7061 Před 5 lety +1

    Can you show how to find value of sigma of 1/(n^n) which n from zero to infinity please!!!

  • @cameronspalding9792
    @cameronspalding9792 Před 5 lety

    When I’m setting up the integral for the arc length: I work out the expression for the inside of the square root first: then square root it

  • @Peter_1986
    @Peter_1986 Před 5 lety +19

    blackpenredpen always has interesting problems in his videos.

  • @Unidentifying
    @Unidentifying Před 5 lety

    maybe you can do a video on the logic behind the sum and difference trigonometric formulas

  • @moadbahron
    @moadbahron Před 5 lety

    MR blackpenredpen
    I have challenge for you which i failed to do it ,the challenge is
    the length between two point on the Ellipsoid by using any coordinating system .

  • @AnnoyingMiner10
    @AnnoyingMiner10 Před 5 lety +1

    There’s an integral in this video so I sure this is relevant enough (maybe...)
    How would one integrate (the indefinite integral of):
    (cos(2x)-1) / x^2
    (I might just be an idiot box)

    • @thebigoeuph
      @thebigoeuph Před 5 lety

      That almost looked like Dirichlet Integral.
      (1-cos(2x))=2sin²x
      So if you make the trigonometric substitution, then you just get
      −2∫(sin²x/x²)
      I don’t know if it has a closed form but if it’s from -∞ to ∞ then you can indeed solve it.

  • @iceymonster4675
    @iceymonster4675 Před 5 lety

    10:44 hmm.. I watch all your content, but am I a true fan even though I haven't done calc since first year uni over 10 years ago? Lol hope so! Love your videos! :D

  • @supriyajyoti22
    @supriyajyoti22 Před 5 lety +1

    Sir plz make video on iit jee problem

  • @patrykszlufik4020
    @patrykszlufik4020 Před 5 lety

    Well I found it. y = r(1-cos (butch(e/r))), where e =x and butch(x) is inverse function of f(x) = t-sin t

  • @jorickleferink7065
    @jorickleferink7065 Před měsícem

    Why do you have to add the x'(t) in the integral?

  • @1412-kaito
    @1412-kaito Před 5 lety

    You know at 10:00 I thought that you showed your true colours but it was near 10:50 actually .
    As for integrals as long as you know the correct method they are easy , like practicing a spooky voice.

  • @exotischematerie1769
    @exotischematerie1769 Před 5 lety

    NICE!

  • @johnsalkeld1088
    @johnsalkeld1088 Před 5 lety

    Really should have pointed out that the answer is the modulus of cos(t/2) but that in the range 0 - 2 pi that this is just cos(t/2)

  • @gergodenes6360
    @gergodenes6360 Před 5 lety +2

    Now let's see what happens if we roll a circle with radius R (not necessarily the original r) on top of a Cycloid, let's see how long will the arch be.

    • @blackpenredpen
      @blackpenredpen  Před 5 lety

      We will get an "epicycloid"
      en.wikipedia.org/wiki/Epicycloid

    • @gergodenes6360
      @gergodenes6360 Před 5 lety

      @@blackpenredpen that is very epic

    • @danieljulian4676
      @danieljulian4676 Před 2 lety

      @@gergodenes6360 And if you build it from a cheese wheel, it's a fol épi cycloid.

  • @danidiaz6343
    @danidiaz6343 Před 2 lety

    How would you calculate the radius of the circle if the point is 64pi cm appart? :(

  • @Patapom3
    @Patapom3 Před 5 lety

    Amazing!

  • @BisyBackson365
    @BisyBackson365 Před 4 lety

    10:45. I think its more difficult but I feel like I have seen it before....

  • @linekerarruda3082
    @linekerarruda3082 Před 3 lety

    Tks BRO Brazil love U

  • @yumi-bv7gf
    @yumi-bv7gf Před 2 lety

    Sir, how to show that a cycloid is periodic?

  • @MrRyanroberson1
    @MrRyanroberson1 Před 5 lety

    Surface area would just be integrating the area multiplied by the y value, so since y = r-rcost, multiplying gives r int(sqrt(2-2cos)*(r-rcos) )dt, which equals sqrt(r) * integral(y^(3/2) dt). using the same double angle formula gives sqrt(r) * 4 * integral(sin^3 (t/2))dt. I guess let u = t/2 real quick to get sqrt(2) * 8 * integral(sin^3 (u))du, and then do that integral that I forgot how to do.

  • @MudruyChannel
    @MudruyChannel Před 5 lety

    I love your videos man. Why sqrt sin^2(t/2) isn't |sin(t/2)|? Also 10:40

    • @manuelnores8653
      @manuelnores8653 Před 5 lety

      I belive it is because sin(t/2) is always positive between 0 and 2π

  • @Melojd50
    @Melojd50 Před 5 lety

    Hi, i love this channel, hey, i need your help with this secuence
    {tan(2/n)/sin(n/2)}, i from Costa Rica, nice to meet you. The question is if converge or diverge.

  • @gauravsuyal4456
    @gauravsuyal4456 Před 5 lety +1

    It all went through out my head because I am a student. But I clicked video to increase views and liked it.😂😂😂

  • @ebrahimalfardan8823
    @ebrahimalfardan8823 Před 5 lety

    Is an isosceles triangle with a sum of interior angles of 3π a circle?

  • @chibigon01
    @chibigon01 Před 5 lety

    Can you apply a similar approach to calculate the area and length of an ellipse?

    • @danieljulian4676
      @danieljulian4676 Před 2 lety

      If I recall correctly, the arc length is an integral that you can only do numerically. No need to recall; you can look this up.

  • @zuccx99
    @zuccx99 Před 5 lety +2

    Epic.

    • @benjaminbrady2385
      @benjaminbrady2385 Před 5 lety +1

      I'm sorry, what is your profile pic from. I keep seeing it everywhere

    • @Swagtorian
      @Swagtorian Před 5 lety +1

      @@benjaminbrady2385 deus ex

  • @jannesl9128
    @jannesl9128 Před 5 lety

    10:46 hehe, true fan hehe. Well I don't know why ur doing that right now, but I'm still having fun at maths so I watch you xD Most I do understand. (Pupil 11th grade) xD

  • @lebronjames1844
    @lebronjames1844 Před 5 lety

    Supposed to be studying for my AP Calculus exam but somehow I ended up here 😂

  • @Lilol100
    @Lilol100 Před 5 lety

    17:36 no absolute value because sin(t/2) >= 0 for t in [0, 2 pi]

  • @lacenabo6950
    @lacenabo6950 Před 3 lety

    Pefect

  • @KalikiDoom
    @KalikiDoom Před 5 lety

    10:50 - I'm a true fence!⸮

  • @matthieumoussiegt
    @matthieumoussiegt Před 3 lety

    1+1=2 and 2*2=4 yes ! that was difficult

  • @nicholasdhaliwal6061
    @nicholasdhaliwal6061 Před 5 lety

    Can you do a video on solids of revolution for rotation about a slant axis (such as y=x)?

    • @danieljulian4676
      @danieljulian4676 Před 2 lety

      Better to wait for linear algebra coordinate transformations.

  • @limerent2883
    @limerent2883 Před 5 lety

    findning area is easier(maybe because i didnt know the formula of arc length:))

  • @MoonLight-sw6pc
    @MoonLight-sw6pc Před 5 lety +1

    Pleas slve this
    The integral of (x^5+1)^10,
    I don't want to spend my life multilpying something to the power of 10
    is there anyway easier .?

    • @justabunga1
      @justabunga1 Před 5 lety

      There’s no other easier way to do this. You would have to multiply it out and using the Pascal’s triangle and then do the integration.

    • @williamperezhernandez7331
      @williamperezhernandez7331 Před 5 lety

      Use binomial theorem. Sum{k=0 to 10} 10!/(k!(10-k)!) (x^5)^k. The integral is Sum{k=0 to 10} 10!/(k!(10-k)!(5k+1)) x^(5k+1). Just evaluate each coefficient to get answer. Don't forget + constant.

    • @muhammadqasim7056
      @muhammadqasim7056 Před 5 lety

      Cant you apply the reverse of the chain rule here.

  • @xxxnicuxxx8269
    @xxxnicuxxx8269 Před 5 lety

    hi, can u help me with an integral, ((1+sen^2 x)/(1-cosx)^2)dx

  • @wompastompa3692
    @wompastompa3692 Před 5 lety

    16:21
    Minus 1, that's 3. #QuickMaths

  • @corridosycorridos7155
    @corridosycorridos7155 Před 5 lety

    Love your videos bro, is there any way I can get in contact with you...??? Do you offer personal tutoring services??

  • @Qoow8e1deDgikQ9m3ZG
    @Qoow8e1deDgikQ9m3ZG Před 5 lety

    and it is too interesting that the result of arc length is a rational number, and don't include pi , any explanation ?

  • @estheranaya4796
    @estheranaya4796 Před rokem

    10:47 im a true fan

  • @wenhanzhou5826
    @wenhanzhou5826 Před 5 lety

    Arclength formula seems more familiar.

  • @SeeTv.
    @SeeTv. Před 3 lety

    3:37 lol

  • @gersonbrandalesi4533
    @gersonbrandalesi4533 Před 4 lety

    2nd part is much harder at 10:32

  • @Crash-yp7ll
    @Crash-yp7ll Před 5 lety

    I was somewhat surprised that the shape is neither an ellipse nor a circle arc, but a 'cycloid' and not a conic... - hmmm - interesting

  • @hurairakhan5757
    @hurairakhan5757 Před 3 lety

    I didn't get the point of 2 pi

  • @solomonbirhane3648
    @solomonbirhane3648 Před 5 lety

    great

  • @thomasplatt7329
    @thomasplatt7329 Před rokem

    i'll meet you outside, Calculus.

  • @TimiAgiri
    @TimiAgiri Před 5 lety

    10:44 harder cuz of the square root
    I’m guessing

  • @Aerospace63
    @Aerospace63 Před 2 měsíci

    10:40 i'm a real one

  • @muhammadqasim7056
    @muhammadqasim7056 Před 5 lety

    Yay finally cycloids, ellipses next?lol

  • @kkente
    @kkente Před 5 lety

    4Head

  • @__shubham__
    @__shubham__ Před 5 lety +1

    Make videos on *JEE Advanced* _Mathematics_ Your subscribers will be more than _T-Series/PewDiePie_ 😉

  • @alse72
    @alse72 Před 5 lety +1

    10:44 watch the whole thing or you won't understand a thing

  • @gaurangkhatavkar968
    @gaurangkhatavkar968 Před 4 lety

    he used blue pen ???

  • @agrajyadav2951
    @agrajyadav2951 Před rokem

    Unexpected fr