Fourier Series of e^x from -pi to pi (fourier series engineering mathematics)

แชร์
ฝัง
  • เผยแพร่เมื่อ 18 ต.ค. 2024

ความคิดเห็น • 149

  • @blackpenredpen
    @blackpenredpen  5 ปีที่แล้ว +60

    Q1. Does the Fouryay Series converge on pi and -pi? Why or why not?
    Q2. What's the sum of 1/(1+n^2) from 1 to inf?
    Be sure to subscribe and let's reach 400k subs by the end of 2019, thank you!!!
    YayYayYayYay

    • @JamalAhmadMalik
      @JamalAhmadMalik 5 ปีที่แล้ว +7

      You'll cross πmillion subscribers this year! 😉

    • @PackSciences
      @PackSciences 5 ปีที่แล้ว +7

      1. I remember the serie expansion is non-continuous in pi and -pi, I don't exactly remember the reasoning.
      2. Dirichlet theorem -> S= (pi cosh(pi) - sinh(pi))/(2 sinh(pi)).

    • @etto487
      @etto487 5 ปีที่แล้ว +1

      Q1 : in the points of discontinuity of f for ex. t the fourier series of f converge to :
      (f(t+) + f(t-))/2
      Q2: to calculate the sum you need to calculate the fourier series in pi or - pi because cos(npi)=(-1)^n=cos(-npi) because cos is an even function.
      f(t+)=lim(x--->t+)(f(x))
      f(t-)=lim(x--->t-)(f(x))

    • @angelmendez-rivera351
      @angelmendez-rivera351 5 ปีที่แล้ว +2

      For Q1: notice that the Fourier series will result in the same infinite series for x = π as for x = -π, yet the function it equals is different. Therefore, for at least one of the endpoints, the Fourier series does not converge. In fact, if I remember correctly, it would instead converge to the average of the function evaluated at the intervals. In other words, it would evaluate to cosh(π). This means cosh(π) = sinh(π)/π + 2•sinh(π)/π•S, where S is the series of 1/(1 + n^2) over all n starting at n = 1. Diving by sinh(π) gives coth(π) = 1/π + 2/π S, so 2S/π = coth(π) - 1/π. Then S = (π/2)coth(π) - 1/2. This answer makes sense given that the integral from x = 1 to x going to infinity of 1/(1 + x^2) is π/2 - π/4, and the sum, although we know it is bigger than this integral, is only bigger by a little bit. Meanwhile, π/4 and 1/2 are comparable in size and relatively close to one another. Also, coth(π) is indeed approximately 1. This is sufficient for us to know that that should be the correct answer.
      Therefore, for Q2: the answer is π·coth(π)/2 - 1/2.

    • @ffggddss
      @ffggddss 5 ปีที่แล้ว +3

      Q1: Do you mean, at x = ±π?
      One famous property of Fourier series (FS) is that, when the limits exist, the series evaluated at any given x, equals the average of its right- and left-limits at that point. Where the FS is a continuous function, this is of course, trivial.
      But when there's a finite discontinuity (a saltus) at x₀ , the graph has an isolated point there, midway between where the right- and left-hand "tails" terminate.
      Let's first rewrite your series, factoring out of the summation, everything independent of n, and then factor things inside the sum:
      F(x) = [(e^π - e^-π)/2π] (1 + 2 ∑₁⁰⁰[(-1)ⁿ/(1+n²)] [cos(nx) - n sin(nx)] )
      = [sinh(π)/π] (1 + 2 ∑₁⁰⁰[(-1)ⁿ/(1+n²)] [cos(nx) - n sin(nx)] )
      Now the FS you've found is for eˣ, on the interval (-π, π), repeated periodically out to ±∞.
      At all the "junctures" - every odd multiple of π - the cos term will be (-1)ⁿ, and the sin term will be 0. So you'll have
      F(π) = F(-π) = F([2k+1]π) = [sinh(π)/π] (1 + 2 ∑₁⁰⁰[1/(1+n²)])
      But the left- and right-limits at each of those points will be e^-π and e^π, so since the FS is everywhere bilateral-limit averaged, and since we know that the FS converges to eˣ for x ∈ (-π, π), it must be
      F(π) = ½(e^π + e^-π) = cosh(π)
      so of course, the FS can't converge to eˣ at the endpoints of your interval.
      And this answers Q2 (Why am I sure you planned it this way?), because we have
      F(π) = [sinh(π)/π] (1 + 2 ∑₁⁰⁰[1/(1+n²)]) = cosh(π) . . . so
      Q2:
      ∑₁⁰⁰[1/(1+n²)] = ½[π cosh(π)/sinh(π) - 1] = ½[π coth(π) - 1] = 1.0737242312844...
      [This answer agrees with PackSciences' and Angel's.]
      As a "sanity check," we can notice by the comparison test, that this series must lie between:
      0 < ∑₁⁰⁰[1/(1+n²)] < ∑₁⁰⁰[1/n²] = ⅙π² = 1.6449340668482...
      and since every term of the former < the corresponding term of the latter, and the leading terms differ by ½,
      ∑₁⁰⁰[1/(1+n²)] < ∑₁⁰⁰[1/n²] - ½ = ⅙π² - ½ = 1.1449340668482...
      Fred

  • @thedoublehelix5661
    @thedoublehelix5661 4 ปีที่แล้ว +21

    Pro tip: if you notice a constant is being used often, give it a name. I took (e^pi - e^(-pi))/pi to be equal to gamma and that cleaned up my work a lot! Also at the end you can notice that gamma = 2sinh(pi)/pi.

  • @natew7336
    @natew7336 4 ปีที่แล้ว +6

    You have been helping me understand math since calculus and I'm in PDE's now. You're a true hero

  • @stumbling
    @stumbling 5 ปีที่แล้ว +5

    You have no idea how much I needed this. Thanks. May Chen Lu be with you.

  • @The1RandomFool
    @The1RandomFool 4 ปีที่แล้ว +8

    Just a minor nitpick: (e^(pi) - e^(-pi))/2 can be abbreviated sinh(pi).

  • @alexander51413
    @alexander51413 5 ปีที่แล้ว +21

    It's interesting to see that if you ignore the sin(nx) term in the expansion, the resulting function is no longer e^x but now cosh(x) (and ignoring a_0 and cos(nx) gives sinh(x)). I guess it makes sense knowing that e^x = cosh x + sinh x and that probably also explains why lots of comments point out that expansion of e^x can be expressed very easily using the hyperbolic trig functions.

    • @crismal6477
      @crismal6477 4 ปีที่แล้ว +1

      That’s awesome, I didn’t even know that. I’m just learning about Fourier series and it’s really cool, I wish I learned about all this earlier.

    • @CharlesPanigeo
      @CharlesPanigeo 3 ปีที่แล้ว +4

      This is not a coincidence! In fact, this is a valid definition of sinh(x) and cosh(x). Every function can be uniquely decomposed as the sum of an even function and an odd function. For e^x that decomposition is e^x = cosh(x) + sinh(x) as you said. Relating that the Fourier series, the cos(x) terms of the Fourier series always describe the even part of the decomposition, and the sin(x) terms always describe the odd part. So we can use the Fourier series to calculate the even-odd decomposition of any function!

  • @jasonryan2545
    @jasonryan2545 4 หลายเดือนก่อน

    This is indeed beautiful. For one, I could never understand why some equations look comparatively more beautiful than others. I can see now that if the correct inputs are in place, the equation does the work for us! Once again though, this is indeed a fantastic series! Thank you do much! ❤🎉

  • @tomvanmoer8202
    @tomvanmoer8202 5 ปีที่แล้ว +4

    This was on my Calculus II exam back in 2011. Those were some good times.

  • @angelmendez-rivera351
    @angelmendez-rivera351 5 ปีที่แล้ว +32

    YAY you made the yay video
    Also, notice that the term A0 is equal to sinh(π)/π. Just thought it was interesting. In fact, you can entirely factor out a multiple of sinh(π)/π from the series.

    • @blackpenredpen
      @blackpenredpen  5 ปีที่แล้ว +3

      Yup, it is! : )

    • @aashsyed1277
      @aashsyed1277 3 ปีที่แล้ว

      yaya yay yay yay series aka fouryay yay ya y ay yatyb series!!!!!!!!!

  • @resident5124
    @resident5124 5 ปีที่แล้ว +4

    This was really cool, I enjoy anything Fourier so seeing this was great. Thanks!

  • @no1bot_in_Dt
    @no1bot_in_Dt ปีที่แล้ว

    This is so nice. Proud to see a Nigerian youth be so creative ❤
    I wish you success in all you are about to embark on.

  • @brightkwofie982
    @brightkwofie982 2 ปีที่แล้ว

    Great Sir, i never understand fourier series till i watched this video, Bravoo

  • @radiotv624
    @radiotv624 5 ปีที่แล้ว +24

    Will you be doing Fourier Transform?

  • @Àlify.11
    @Àlify.11 8 หลายเดือนก่อน

    Hello sir I'm from India
    This was extremely good...
    Thank you

  • @varshiniarunkumar5643
    @varshiniarunkumar5643 4 ปีที่แล้ว +2

    Thank you sir....This sum was asked in my internals exam....Now i got this sum clear

    • @kevinzenith
      @kevinzenith 4 ปีที่แล้ว

      Hands down. Me too! 😂😅

  • @ok-gl7eq
    @ok-gl7eq 2 ปีที่แล้ว +1

    Thanks helped a lot

  • @jokinnn
    @jokinnn 2 ปีที่แล้ว

    thanks, nice trick on the integral

  • @horsehorse1791
    @horsehorse1791 ปีที่แล้ว

    Bro you are great yaar
    Just keep working
    I appreciate your work 👍👍

  • @stephomn
    @stephomn 5 ปีที่แล้ว

    that was an amazing result looking forward to more awesome results thanks for sharing and keep it up

  • @siggea5912
    @siggea5912 2 ปีที่แล้ว

    Thanks for the video!

  • @chimaru8943
    @chimaru8943 5 ปีที่แล้ว +3

    you're a life saver BPRP #yay

  • @ozzyfromspace
    @ozzyfromspace 4 ปีที่แล้ว +1

    Math for its own sake is a beautiful thing, gotta say ❤️

  • @Rajgorabhijeet
    @Rajgorabhijeet 5 ปีที่แล้ว +1

    Thankyou sir,
    B. Engineering
    Learning from India .

  • @sahanravindu7828
    @sahanravindu7828 ปีที่แล้ว

    thank you sir

  • @Patapom3
    @Patapom3 5 ปีที่แล้ว +2

    Amazing!

  • @krishnak.dileep4120
    @krishnak.dileep4120 3 หลายเดือนก่อน

    Thank you so much.... You are like God to me

  • @nancysharma9454
    @nancysharma9454 5 ปีที่แล้ว

    I like the way you teach .....

  • @jeffreyluciana8711
    @jeffreyluciana8711 4 ปีที่แล้ว

    Excellent!

  • @shivadahiya1914
    @shivadahiya1914 5 ปีที่แล้ว

    Thanks bro u make my day

  • @الملكهالمغروره-ك4غ
    @الملكهالمغروره-ك4غ 5 ปีที่แล้ว

    Thank you

  • @maxwellsequation4887
    @maxwellsequation4887 4 ปีที่แล้ว +1

    Intense

  • @NicolasSchmidMusic
    @NicolasSchmidMusic 4 ปีที่แล้ว +8

    it scared me when those children started yaying

  • @abdallahallahham8586
    @abdallahallahham8586 5 ปีที่แล้ว

    This is amazing ... thank you

  • @kamosevoyan4370
    @kamosevoyan4370 5 ปีที่แล้ว

    Ты великолепный человек, спасибо большое!

  • @camilomuianga7865
    @camilomuianga7865 ปีที่แล้ว

    Why do we have to integrate a none periodic function in the interval [-pi, pi]?

  • @nctbeducation3042
    @nctbeducation3042 6 หลายเดือนก่อน

    Thanku bro

  • @buzeaalexandru4769
    @buzeaalexandru4769 5 ปีที่แล้ว

    Your videos about calculus are really cool man. I learned a lot from them. Can you do the limit as x approaches 0+ of x^(e^-1/x) in your next video?

    • @angelmendez-rivera351
      @angelmendez-rivera351 5 ปีที่แล้ว +1

      Buzea Alexandru L = lim (x -> 0+) x^(e^-1/x). log L = log [lim (x -> 0+) x^(e^-1/x)] = lim (x -> 0+) e^(-1/x)•log x, since log x is a continuous function on the interval (0, ♾). e^(-1/x)•log x = log x/[e^(1/x)], so log L = lim (x -> 0+) log x/[e^(1/x)] = lim (x -> 0+) (1/x)/[e^(1/x)•(-1/x^2)] = - lim (x -> 0+) x/[e^(1/x)] = 0, since the form is 0+/e^+Infinity = 0/infinity = 0. Hence log L = 0, so L = 1, and since L = lim (x -> 0+) x^(e^(-1/x)), this means lim (x -> 0+) x^[e^(-1/x)] = 1

  • @NeonArtzMotionDesigns
    @NeonArtzMotionDesigns 5 ปีที่แล้ว

    I ended up getting a 4 on the AP calculus ab

  • @DC-zi6se
    @DC-zi6se 2 ปีที่แล้ว

    Step jumps are there

  • @angelmendez-rivera351
    @angelmendez-rivera351 5 ปีที่แล้ว +1

    Also, I know you said the Fourier series does not converged at the endpoints. But I did notice that if you let x = π, then the sin(n•x) all become 0, and cos(nπ) = (-1)^n, and if you multiply that by the coefficient (-1)^n/(1 + n^2), then the result is 1/(1 + n^2). So this would give you the sum, assuming the series were to converge to the function at the endpoints. But the problem is that it also works for x = -π,, and that seems to give a contradiction since the series would stay exactly the same, but the thing it equals would be different. It is a pity.

    • @blackpenredpen
      @blackpenredpen  5 ปีที่แล้ว

      Angel Mendez-Rivera
      Yes, I actually said the exact thing when I recorded the video but decided to cut that off to shorten the length. The interesting thing is, sum of 1/(1+n^2) is equal to the average when we plug Pi and -Pi in. Crazy and I don't know why!

    • @angelmendez-rivera351
      @angelmendez-rivera351 5 ปีที่แล้ว

      blackpenredpen ooh I used to know th explanation but I forgot it. It had something to with this one phenomenon that caused the oscillation to go crazy near the endpoints

    • @danielauto3767
      @danielauto3767 5 ปีที่แล้ว +1

      No, not a pitty. The end points do converge. They just don't converge to the the values of the function at either end. Both ends converge instead to the average of the function values calculated at the end points.

    • @danielauto3767
      @danielauto3767 5 ปีที่แล้ว +1

      It's called Gibbs phenomenon. Look it up

    • @angelmendez-rivera351
      @angelmendez-rivera351 5 ปีที่แล้ว

      Daniel Auto Yeah, I actually realized that before you commented, and I posted in my long response to the comment in he asked the questions

  • @purim_sakamoto
    @purim_sakamoto 3 ปีที่แล้ว

    お疲れ様でした
    Yes! Say! Fouriyay!

  • @shazullahyusufzai5704
    @shazullahyusufzai5704 11 หลายเดือนก่อน

    Could you please solve this equation x^x=e

  • @victorpaesplinio2865
    @victorpaesplinio2865 3 ปีที่แล้ว

    I did the same thing, but for the complex version of the series.
    I got
    Sum from -infinity to infinity of sinh(pi)/pi (-1)^n e^(i*n*t)
    All the steps to find the complex coefficient are consistent, but Wolfram Alpha and others sums calculators says this sum diverges.
    Is this result consistent? I know this videos is more than 2 years old, but I didn't find the complex version of e^x series anywhere on internet.

  • @mafujmolla5069
    @mafujmolla5069 2 ปีที่แล้ว

    Great💚

  • @zedzad3279
    @zedzad3279 4 ปีที่แล้ว

    Dear Sir , Can you explain how you get the integration of a0 and a n to the power n ??? please

  • @aniketmunde5733
    @aniketmunde5733 2 ปีที่แล้ว

    tq

  • @shin81able
    @shin81able 3 ปีที่แล้ว

    nice video :) what happens if its e^(x-pi) how to calculate this?

  • @zabrakhan5178
    @zabrakhan5178 5 ปีที่แล้ว +2

    How would you visualize this when looking at the graphs of both e^x and the Fourier series of e^x?

    • @angelmendez-rivera351
      @angelmendez-rivera351 5 ปีที่แล้ว +3

      Zabra Khan The Fourier series takes that segment and the repeats it periodically, resulting in discontinuities at every multiple of π. It repeats it at the same height.

    • @ffggddss
      @ffggddss 5 ปีที่แล้ว +4

      @@angelmendez-rivera351 Right, except the discontinuities are at every odd multiple of π.
      Fred

    • @angelmendez-rivera351
      @angelmendez-rivera351 5 ปีที่แล้ว +1

      ffggddss Correct, that is what I meant to say.

  • @kartiksharma7166
    @kartiksharma7166 5 ปีที่แล้ว

    Pls do a video on the summation of
    x+ x^2 +x^4 + x^8+x^16 ... (inf)
    Yayayayayayayayayayayayayaya......👍👍👍👍👌👌👌👌this video deserves 💐💐💐💐

  • @sugarfrosted2005
    @sugarfrosted2005 5 ปีที่แล้ว

    I get it, you're assuming that it has a form then extracting the form using linear operators.

    • @angelmendez-rivera351
      @angelmendez-rivera351 5 ปีที่แล้ว

      sugarfrosted He is assuming it can be expressed as a linear combination of the basis space of waves.

  • @thomasblackwell9507
    @thomasblackwell9507 5 ปีที่แล้ว

    COOL!

  • @zakichahboun543
    @zakichahboun543 3 ปีที่แล้ว

    hello brother i have a question Can I replace e ^ (π) -e ^ (- π) with sinh (π) ?????

  • @i_am_anxious0247
    @i_am_anxious0247 5 ปีที่แล้ว +1

    200K (almost) subs #YAY
    Among the last of the good creators at the heart of this platform #YayYayYayYay
    :)))

    • @blackpenredpen
      @blackpenredpen  5 ปีที่แล้ว +1

      Pi is the best 😁😁😁😁😁thank you!!!

    • @i_am_anxious0247
      @i_am_anxious0247 5 ปีที่แล้ว

      blackpenredpen 😁😁

  • @ffggddss
    @ffggddss 5 ปีที่แล้ว +1

    I concur that this deserves 4 yay's!
    Fred

  • @luisgamalielbasurtocavazos6076
    @luisgamalielbasurtocavazos6076 5 ปีที่แล้ว

    Thanks you just saved my life lol

  • @sciencebyoliver6888
    @sciencebyoliver6888 4 ปีที่แล้ว

    is this on a open interval from -pi to pi????

  • @rameshparamanikofwestbenga1742
    @rameshparamanikofwestbenga1742 5 ปีที่แล้ว

    Right a0/2

    • @Bayerwaldler
      @Bayerwaldler 4 ปีที่แล้ว

      There are different definition for a0. The one bprp uses contains the factor 1/2.

  • @rshawty
    @rshawty 3 ปีที่แล้ว

    azy j’ai lâché un like juste pour le début chu un gamin mdrr
    yaaaaaay

  • @owamaraayomide8597
    @owamaraayomide8597 3 ปีที่แล้ว

    Why is cos(-nπ)=(-1)^n and cos(nπ)=(-1)^n

  • @kutuboxbayzan5967
    @kutuboxbayzan5967 5 ปีที่แล้ว

    Well i understanded proof but 1 think is not true
    e^-pi=lim x->-pi (f(x))=sum An*cos(nx)+bnsin(nx)=-sum An
    e^pi= lim x->pi(f(x))=sum Ancos(nx)+Bnsin(nx)=-sum An
    And this meaning e^-pi=e^pi then pi=0.
    Can you say my wrong?

  • @sanzao7487
    @sanzao7487 5 ปีที่แล้ว

    Dude,
    ty!! when i was practicing, i thought that -pi in Sen(kx)-->(Senk-pi) it could not use the identity :c
    Viva!

  • @miotegui
    @miotegui 5 ปีที่แล้ว

    Could be possible that you made a mistake on the a0?. Shouldn't it be a0 = (e^pi - e^-pi)/pi ?

    • @Bayerwaldler
      @Bayerwaldler 4 ปีที่แล้ว +1

      There are different definition for a0. The one bprp uses contains the factor 1/2.

    • @miotegui
      @miotegui 4 ปีที่แล้ว

      @@Bayerwaldler Thanks!

  • @Jacob-uy8ox
    @Jacob-uy8ox 5 ปีที่แล้ว +1

    Tetration of yays!

  • @azharshah1397
    @azharshah1397 3 ปีที่แล้ว

    Sir, can't we use the hyperbolic functions in this problem?

  • @_DD_15
    @_DD_15 5 ปีที่แล้ว

    Lol I was gonna say why didn't you use sinh (pi), then I saw that your goal was something totally differe than showing the terms of e^(x) in terms of cos and sin.

  • @soumyaranjanbehera5295
    @soumyaranjanbehera5295 4 ปีที่แล้ว

    is cosnπ is equal to cos(-nπ) ,

  • @apoorvvyas52
    @apoorvvyas52 5 ปีที่แล้ว

    How to deal if the interval is between say any two numbers a and b rather than - pi to pi?

  • @anntphone7727
    @anntphone7727 ปีที่แล้ว

    How get 1 power n

  • @shivimish9962
    @shivimish9962 5 ปีที่แล้ว

    How do you test anything for convergence?

  • @ccuuttww
    @ccuuttww 5 ปีที่แล้ว

    the problem is why we need to approximate the e?

    • @blackpenredpen
      @blackpenredpen  5 ปีที่แล้ว

      I actually have been wanting to do that sum of (-1)^n/(1+n^2) so that's why I do these.

  • @VikasSingh-tw8wu
    @VikasSingh-tw8wu 5 ปีที่แล้ว

    But the formula for fourier serious also includes 1/2 a0 ...which you didn't write

    • @Bayerwaldler
      @Bayerwaldler 4 ปีที่แล้ว

      There are different definition for a0. The one bprp uses contains the factor 1/2.

  • @yossefbudagov8748
    @yossefbudagov8748 5 ปีที่แล้ว

    Could you make a video proving the 1/pi approxiamation?

  • @emperorpingusmathchannel5365
    @emperorpingusmathchannel5365 5 ปีที่แล้ว +1

    Intuitive proof for taylor and fourier series?

    • @angelmendez-rivera351
      @angelmendez-rivera351 5 ปีที่แล้ว +1

      GLaDOS What exactly do you mean by proving them? They are definitions.

    • @nathanisbored
      @nathanisbored 5 ปีที่แล้ว

      @@angelmendez-rivera351 they are not definitions, and he just proved them in a couple previous videos

    • @angelmendez-rivera351
      @angelmendez-rivera351 5 ปีที่แล้ว +1

      nathanisbored He did not prove them. He explained what they are, why we want them, and how to get them.

    • @nathanisbored
      @nathanisbored 5 ปีที่แล้ว

      @@angelmendez-rivera351 if they were just definitions, then we couldnt use them to derive other things about the functions they represent. for example we wouldnt be able to say the identity he showed at the end of the video is true. we can however define them to be extensions of the domain of a function (for example e^(ix) can be evaluated using the taylor series as a definition)

    • @angelmendez-rivera351
      @angelmendez-rivera351 5 ปีที่แล้ว +1

      nathanisbored Your comment makes absolute nonsense, considering that everything in mathematics can only be derived from axioms and definitions. The definition of the Taylor series of a function f(x) is the power series with respect to x - a with the coefficient sequence [f^(n)](a)/n!. That has nothing to do with whether there is information about the function we can derive from this series or not. The series already uses information about the function inevitably. The reason we define e^x by its Taylor series is because the function is analytic and the series converges uniformly everywhere, so it occupies the same real domain as the previous definition, but with much more convenience of usage, and this analicity gives a continuation which permits for using this for complex numbers and elements of other topological spaces. That once again has nothing to do with these series being definitions and not theorems.

  • @jinijophy2974
    @jinijophy2974 5 ปีที่แล้ว

    How did (1+n)^2 become 1+n^2?

    • @ffggddss
      @ffggddss 5 ปีที่แล้ว +1

      It didn't. 1/(1 + n²) came from the factor of 1/(a² + b²) in the integrals, ∫eªˣ sin(bx) dx and ∫eªˣ cos(bx) dx; with a=1, b=n.
      Fred

  • @jyotirmoyroy7041
    @jyotirmoyroy7041 4 ปีที่แล้ว

  • @johnk3841
    @johnk3841 5 ปีที่แล้ว

    I like foyay

  • @osuNoobCast
    @osuNoobCast 5 ปีที่แล้ว

    13:15 what else would i like? i

  • @greggregi6383
    @greggregi6383 5 ปีที่แล้ว +1

    you got some big arms

    • @gian2kk
      @gian2kk 5 ปีที่แล้ว

      Do you even lift bro

  • @adarshkumar3184
    @adarshkumar3184 5 ปีที่แล้ว +2

    Hello ,did you the exact integral of (root over tan(X) +root over cot(X))dx . Please help me guy i'm in trouble

    • @angelmendez-rivera351
      @angelmendez-rivera351 5 ปีที่แล้ว

      adarsh kumar What is that expression supposed to mean? More specifically, what exactly is “root over tan(x)”?

    • @adarshkumar3184
      @adarshkumar3184 5 ปีที่แล้ว +1

      No friend , it is integral of (√(tan(x))+√(cot(x)) dx which is to be determined

    • @angelmendez-rivera351
      @angelmendez-rivera351 5 ปีที่แล้ว

      adarsh kumar He already has a video on these. More specifically, he made a video on integrating the SqRt[tan(x)]. That answers half your question. As for SqRt[cot(x)], notice that cot(x) = tan(π/2 - x). As such, all you must do is perform the substitution u = π/2 - x, and your integrand will simply become a constant multiple of SqRt[tan(u)], and that answers the second part to your question.

    • @adarshkumar3184
      @adarshkumar3184 5 ปีที่แล้ว

      @@angelmendez-rivera351 thanks a lot

    • @adarshkumar3184
      @adarshkumar3184 5 ปีที่แล้ว

      @@angelmendez-rivera351 I've one more question that is integral of 1over (sin^4(x) +sin^2(X) cos^2(X) +cos^4(x)) whole multiple dx

  • @copperfield42
    @copperfield42 5 ปีที่แล้ว +1

    :o this is more cute than the mess I got XD
    I didn't simplify those cos(nπ) and sin(nπ), but I transformed those exponential into sinh(π)

  • @JamalAhmadMalik
    @JamalAhmadMalik 5 ปีที่แล้ว +2

    #yay
    I am a wannabe mathfreak!

  • @daniellazar4742
    @daniellazar4742 5 ปีที่แล้ว

    Can you integrate (ln(1/x)+sqrt(x))/(x^2+sin(1/x^2)) ?

    • @angelmendez-rivera351
      @angelmendez-rivera351 5 ปีที่แล้ว

      I am fairly certain this is not integrante using elementary functions.

  • @sub2sub900
    @sub2sub900 4 ปีที่แล้ว

    wrong