incredible sin sin sum

incredible sin sin sum. I calculate the sum of sin/n! using complex exponentials, Euler’s formula, power series and Taylor series. This was recommended by Steven strogatz from Cornell and is a must see for any complex analysis and calculus student. This is a beautiful result whose answer involves sin sin, the composition of trigonometric functions
Subscribe to my channel: / drpeyam
TikTok: / drpeyam
Instagram: / peyamstagram
Teespring merch: teespring.com/stores/dr-peyam

Пікірлер: 54

  • @bartomiejpotaman6973
    @bartomiejpotaman6973 Жыл бұрын

    I honestly aspire to be as happy as you are doing maths

  • @loicetienne7570
    @loicetienne7570 Жыл бұрын

    Thank you, that is a lot of fun, as ever. Possible inaccuracy: The power series of the exponential begins at n = 0 I believe, in which case a -1 term would be missing, which, however, does not affect the final result (since the real part is discarded).

  • @drpeyam

    @drpeyam

    Жыл бұрын

    Yeah the original sum was meant to be from n = 0

  • @olbluelips
    @olbluelips Жыл бұрын

    Nothing more satisfying than expressing a infinite sum in terms of transcendental functions!

  • @JohnPretty1
    @JohnPretty1 Жыл бұрын

    Dr Peyam, thank you very much!

  • @shahinjahanlu2199
    @shahinjahanlu2199 Жыл бұрын

    سال نو مبارک دکتر پیام. برایتان سالی سرشار از زیبایی و سلامت و برکت آرزومندم

  • @kasparovmarconi2608
    @kasparovmarconi2608 Жыл бұрын

    bien hecho dr peyam saludos de Perú.

  • @drpeyam

    @drpeyam

    Жыл бұрын

    Gracias!!

  • @ekadria-bo4962
    @ekadria-bo4962 Жыл бұрын

    When you make something complex and surprisely it become more easy 😁🤭

  • @kharnakcrux2650
    @kharnakcrux2650 Жыл бұрын

    o_o;;; this is such a thrill. Seeing this performed by someone else. Back in college... i used to tinker with the Flint Hills series. bizarre series where integers go into Trig functions, just like this. i wonder if you could perhaps give it some exploration. But.... my suggestion, try looking at it in terms of the group symmetries involved. These complex methods i've seen you use... really opened my eyes again! It's very empowering. I want to dive back in and try a few things.

  • @General12th
    @General12th Жыл бұрын

    Hi Dr. Peyam! Very cool!

  • @ruud9767
    @ruud9767 Жыл бұрын

    A nice one!

  • @nzshera203
    @nzshera203 Жыл бұрын

    i wanna b as happy as u while doin maths :)

  • @alejrandom6592
    @alejrandom659211 ай бұрын

    Similiar things appear when solving y^(n) - y = 0

  • @JuanLara18
    @JuanLara18 Жыл бұрын

    I'm a big fan of your videos. I just wanted to point out a small mistake. The series actually starts at n=0, so the sum of x^n/n! is equal to e^x-1. This doesn't affect the result for sin, as it corresponds to the imaginary part, but for cosine it does make a difference.

  • @drpeyam

    @drpeyam

    Жыл бұрын

    Thx

  • @kobethebeefinmathworld953
    @kobethebeefinmathworld953 Жыл бұрын

    0:26 Das ist schön!

  • @CornishMiner
    @CornishMiner Жыл бұрын

    No way! So cool 😎

  • @user-fy5tn7sy3t
    @user-fy5tn7sy3t Жыл бұрын

    Thank u doctor and thank you for " uwylar identity "

  • @addoul99
    @addoul99 Жыл бұрын

    Can someone help me understand. I thought e^(iN) = cos(N) + isin(N)….so how come at the beginning he replaced sin(N) with e^iN without handling the cosine ?

  • @drpeyam

    @drpeyam

    Жыл бұрын

    Correct, because you can compare imaginary parts

  • @rodrigolopez3874
    @rodrigolopez3874 Жыл бұрын

    I've a christmas problem for you, I've a christmas tree (a cone height h and base radius r) and I want to decorate it with a strip of lights, how long it needs to be to do n complete laps around the tree while going down ending in the bottom? I think is a curious problem, I dont know if its very difficult or messy but looks fun. Anyway happy christmas!!

  • @drpeyam

    @drpeyam

    Жыл бұрын

    That does sound interesting! It would have to wait til next Xmas though hahaha

  • @dp121273
    @dp121273 Жыл бұрын

    EIN Dr. Peyam pro Tag würde mein Leben reicher machen! Ja, neee, bin zwar ein Mann, aber trotzdem ... Liebe deine Videos und deinen Humor 🥰

  • @drpeyam

    @drpeyam

    Жыл бұрын

    Awwwwww

  • @pcrdeg
    @pcrdeg Жыл бұрын

    The index of sum is 0 no 1. The result is correct. Thanks for yours videos.

  • @orenfivel6247

    @orenfivel6247

    Жыл бұрын

    0:50 not precisely. result is correct since sin(0)/0!=0/1=0

  • @sebmata135

    @sebmata135

    Жыл бұрын

    sin(0) = 0 so I fail to see how it matters

  • @wulli_

    @wulli_

    Жыл бұрын

    I believe what is meant is, that the power series definition of the exponential function starts at index 0 and not 1, as opposed to the video. Coincidentally, the result is still correct, as the omitted first term corresponding to the index 0, namely ((e^i)^0)/0! = 1, does not contribute to the imaginary part of the sums value.

  • @drpeyam

    @drpeyam

    Жыл бұрын

    Thank you, and yeah it really doesn’t matter

  • @pietergeerkens6324

    @pietergeerkens6324

    Жыл бұрын

    @@drpeyam I hope you don't mind: I've been using you (as well as myself) as examples for my math tutees when they make a careless algebra error: "Algebra is hard, and finicky, to get right. Everyone makes careless errors in the algebra, at least occasionally. I make them (in high school, like the wake of a cruise ship I made them); and even Dr. Peyam on KZread occasionally makes careless errors. The trick is to practice finding the errors, since they're always lurking somewhere."

  • @aneeshsrinivas9088
    @aneeshsrinivas9088 Жыл бұрын

    0:23, you got ein eh? Insert cowboy bebop reference here.

  • @greghansen38
    @greghansen38 Жыл бұрын

    The more languages you know, the more words you can find in your equations.

  • @ikramefa2019
    @ikramefa2019 Жыл бұрын

    Hi I think the sum will start from N = 0 not 1 ?

  • @drpeyam

    @drpeyam

    Жыл бұрын

    Yes but doesn’t matter

  • @quanticansh
    @quanticansh Жыл бұрын

    how'd you write sin(N) as e^iN ?

  • @jadewolf3416

    @jadewolf3416

    Жыл бұрын

    Agreed. I thought writing sin(N) as complex definition is (e^(iN)-e^(-iN))/2i? Or maybe there are some cancellations that were omitted?

  • @fedebic5443

    @fedebic5443

    Жыл бұрын

    He didn't, if you watch the entire video you can see that he is just building a "similar" problem with e^(iN) (which, like you mentioned, isn't the same as sin(N)) and at the end considers only the imaginary part of the solution, which corresponds to the solution of the original problem (because sin(N) is the imaginary part of e^(iN))

  • @HershO.

    @HershO.

    Жыл бұрын

    you need to watch till the end to actually understand what he did. Edit : thought I'd mention that he uses the fact that Im(e^ix) = sin(x) which comes from Euler's formula

  • @drpeyam

    @drpeyam

    Жыл бұрын

    exp(in) = cos(n) + i sin(n) and then you take imaginary parts

  • @TheMichaelmorad
    @TheMichaelmorad Жыл бұрын

    A good question for Hanukkah

  • @geraltofrivia9424
    @geraltofrivia9424 Жыл бұрын

    Wow

  • @brendanlawlor2214
    @brendanlawlor2214 Жыл бұрын

    hermosa

  • @user-cg3vy5zs8d
    @user-cg3vy5zs8d Жыл бұрын

    Симпатичный ряд

  • @IoT_

    @IoT_

    Жыл бұрын

    Ага. И решается просто.

  • @michaeljagdharry
    @michaeljagdharry Жыл бұрын

    When you said e i e i o LMAO!!!!!

  • @respondepuh
    @respondepuh Жыл бұрын

    pero la suma parte de n=0. Como estudiante, esos detalles cuestan puntaje en una prueba

  • @drpeyam

    @drpeyam

    Жыл бұрын

    No importa, sin(0) = 0

  • @respondepuh

    @respondepuh

    Жыл бұрын

    @@drpeyam me respondió en español!!

  • @MrSirBossmanChief
    @MrSirBossmanChief Жыл бұрын

    Wait isn’t sin(N) = (exp(iN) + exp(-iN)) / 2i

  • @drpeyam

    @drpeyam

    Жыл бұрын

    But also sin = Im exp

  • @orenfivel6247

    @orenfivel6247

    Жыл бұрын

    that's cos(N)

  • @stefan11804
    @stefan11804 Жыл бұрын

    Nice german

  • @drpeyam

    @drpeyam

    Жыл бұрын

    Danke!!