i-th root of i

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  • เผยแพร่เมื่อ 24 ธ.ค. 2024

ความคิดเห็น • 611

  • @blackpenredpen
    @blackpenredpen  ปีที่แล้ว +32

    Do you enjoy complex numbers and up for a challenge? If so, check out x^x=i th-cam.com/video/vCdChDmMYL0/w-d-xo.html

    • @vincentkingsdale8334
      @vincentkingsdale8334 ปีที่แล้ว

      How is this practically applied to real life????

    • @Unlimit-729
      @Unlimit-729 7 หลายเดือนก่อน

      You can't solve subfactorial of i.

  • @pseudotenshi3431
    @pseudotenshi3431 3 ปีที่แล้ว +411

    The most surprising thing about this is
    I understood more than half of what he explained

  • @hyperpsych6483
    @hyperpsych6483 5 ปีที่แล้ว +1307

    0:32
    "I don't like to be on the bottom, I like to be on the top"
    Me: *scrolls down to comments to see if anyone made a joke about that*

    • @hendrik5919
      @hendrik5919 5 ปีที่แล้ว +9

      A joke would be like what?

    • @TheLifeofJay1
      @TheLifeofJay1 5 ปีที่แล้ว +28

      Super Psych that is literally exactly what I just did 😂😂😂 you made my day

    • @paulgoogol2652
      @paulgoogol2652 5 ปีที่แล้ว +9

      I assume the top would be the video section, while the bottom is the comment section.

    • @rogerkearns8094
      @rogerkearns8094 5 ปีที่แล้ว +4

      In the video it's already meant to be a joke.

    • @kabochaVA
      @kabochaVA 5 ปีที่แล้ว +16

      Same here...
      0:32 "That's what she said!" xD

  • @michaelliu8887
    @michaelliu8887 4 ปีที่แล้ว +1302

    *Learns about imaginary numbers*
    TH-cam:
    What's 1/i?
    What's e^i?
    What's i^i?
    What's sqrt(i)?
    What's log(i)?
    What's i-th root of i?
    What's sin i?
    What's sin-1(2)?
    What's i factorial?
    What's integral of x^i?

    • @blackpenredpen
      @blackpenredpen  4 ปีที่แล้ว +139

      刘颢云 lolll

    • @Ramu-10
      @Ramu-10 4 ปีที่แล้ว +50

      Ya got lucky...
      I haven't even learned about logarithms and have no clue what e is...

    • @papaganush420
      @papaganush420 4 ปีที่แล้ว +31

      @@Ramu-10 you gotta love when you figure out whats going on

    • @valeriolocatelli665
      @valeriolocatelli665 3 ปีที่แล้ว +21

      @@Ramu-10 it is euler's number, which approxamatly is 2.71.......

    • @nuzlock4481
      @nuzlock4481 3 ปีที่แล้ว +9

      @@Ramu-10 then watch this amazing video about "e" and it's derivation.
      th-cam.com/video/m2MIpDrF7Es/w-d-xo.html

  • @dallasboringnews7157
    @dallasboringnews7157 5 ปีที่แล้ว +1052

    "i" understand this a whole lot better now.

  • @willy3506
    @willy3506 6 ปีที่แล้ว +782

    Do the e-th root of i and the i-th root of e

    • @lyrimetacurl0
      @lyrimetacurl0 5 ปีที่แล้ว +60

      The second one is easy:-
      e^(i*pi) = -1
      ith root of e = e^(1/i)
      So (ith root of e)^(pi*i^2) = -1
      So (ith root of e)^-pi = -1
      Flip over fraction
      So (ith root of e)^pi = -1
      We know e^(i*pi) = -1
      So (ith root of e) = e^i
      That's a distance of 1 radian around the unit circle
      So (ith root of e) = cos(1)+i*sin(1)
      Or about 0.54030 + 0.84147i

    • @anselmschueler
      @anselmschueler 5 ปีที่แล้ว +20

      just go on wolfram|alpha

    • @camerongray7767
      @camerongray7767 5 ปีที่แล้ว +1

      Lyri Metacurl
      Lol

    • @dnpendown3199
      @dnpendown3199 5 ปีที่แล้ว +7

      @@anselmschueler wtf

    • @anselmschueler
      @anselmschueler 5 ปีที่แล้ว +4

      @@dnpendown3199 Or use Qalculate, the best desktop and command line calculator available!
      > root(i,e), root(e,i)
      [root(i, e), root(e, i)] = approx. [0.8376315 + 0.54623573i, 0.54030231 - 0.84147098i]

  • @austinlincoln3414
    @austinlincoln3414 3 ปีที่แล้ว +122

    “I dont like to be on the top. I like to be on the bottom” - blackpenredpen

  • @obinnanwakwue5735
    @obinnanwakwue5735 7 ปีที่แล้ว +320

    Wow, complex roots of imaginary numbers are real......math is so weird!

    • @ffggddss
      @ffggddss 7 ปีที่แล้ว +9

      Sometimes they are, but not usually.

    • @stranger0152
      @stranger0152 7 ปีที่แล้ว +68

      But bro real root of real numbers is also imaginary. For example square root of -1 😂

    • @gaeb-hd4lf
      @gaeb-hd4lf 4 ปีที่แล้ว +8

      @Smash Boy Yeah, technically speaking Complex numbers are just an algebraic estructure made from real numbers (just like matrices for example) so it makes sense that if you apply a function to an "imaginary" number (a number on the Y axis of the complex plane) it gives you a "real" number (a number on the X axis of the complex plane).

    • @philiptymon3380
      @philiptymon3380 4 ปีที่แล้ว +13

      because “One of the miseries of life is that everybody names things a little bit wrong.” - Richard Feynman 1985.

    • @saswatsarangi6669
      @saswatsarangi6669 4 ปีที่แล้ว +1

      Purely imaginary in this case, imaginary root of imaginary...

  • @Fematika
    @Fematika 7 ปีที่แล้ว +14

    The reason why i^i = e^(-pi/2) is because i^i = e^(log(i)i) = e^((pi/2)i * i) = e^(-pi / 2). There are infinite answers because the log(z) has infinite answers; as it is defined as ln |z| + arg(z)i, where arg(z) is the angle (which can be, in this case, pi/2, 5pi/2, 7pi/2, ...).

    • @jco6345
      @jco6345 7 ปีที่แล้ว +1

      but why log(i)=(pi/2)i ?

    • @angelmendez-rivera351
      @angelmendez-rivera351 6 ปีที่แล้ว +2

      J CO Because log(-1) = iπ and -1 = i^2

  • @Rose-vb4wk
    @Rose-vb4wk 7 ปีที่แล้ว +125

    Or you could just
    i = e^(iπ/2)
    ith root both sides
    i√i = e^(π/2)

    • @arthurmoiret6076
      @arthurmoiret6076 3 ปีที่แล้ว +2

      +2kπ ?

    • @dns911
      @dns911 3 ปีที่แล้ว +8

      @@arthurmoiret6076 That's the point when he said there are infinitely many solutions to this

    • @adityasharma2380
      @adityasharma2380 3 ปีที่แล้ว

      I did that too!!!!!

    • @diegocabrales
      @diegocabrales 3 ปีที่แล้ว

      @@arthurmoiret6076 or -2kπ

  • @suryanshkhatri7929
    @suryanshkhatri7929 4 ปีที่แล้ว +6

    This guy rekindles our faith in the fact that things that seem to be very tough, are actually very easy, we just need to take one right step, and everything else becomes so easy!

  • @cangursoy
    @cangursoy 7 ปีที่แล้ว +12

    I just stumbled upon your videos while procrastinating. You're a really warm and enthusiastic talker, keep it up sir! :)

  • @SNOWgivemetheid
    @SNOWgivemetheid 8 หลายเดือนก่อน +1

    I did some other method : Consider i^(1/i) and get i = (-1)^(1/2) and -1=e^iπ so finally : i=e^(iπ/2) so in the end we have i^(π/2) as the "i"s cancel out !

  • @harrisonoberg8085
    @harrisonoberg8085 3 ปีที่แล้ว +1

    i blinked and he got pi out of seemingly nowhere

  • @davidkippy101
    @davidkippy101 7 ปีที่แล้ว +10

    You could actually just start with e^(ipi)=-1. Take the square root of both sides: e^(ipi/2)=i. Then take the ith root of both sides. e^(pi/2)= i^(1/i).

  • @isavenewspapers8890
    @isavenewspapers8890 3 ปีที่แล้ว +2

    Euler’s number and pi, name a more iconic duo

  • @krimbus123
    @krimbus123 ปีที่แล้ว +2

    Another way to do this is using De Moivre’s theorem, where i on the complex plane would be pi/2, so theta is pi/2/i, so e^i theta would simplify to e^pi/2

  • @trip_on_earth
    @trip_on_earth 6 ปีที่แล้ว +38

    I'm in love with mathematics now

    • @D1M1T
      @D1M1T 3 ปีที่แล้ว +4

      I was in love with math. Then they said “do specialists”

  • @rolexmarcelo3218
    @rolexmarcelo3218 3 ปีที่แล้ว +7

    I'm even more amazed that you can formulate these math questions with answers.

  • @notthefez3634
    @notthefez3634 3 ปีที่แล้ว +1

    I just wasted 2 minutes being confused by a problem I never even knew existed and still don't understand

    • @WorriedtheCircusDemon
      @WorriedtheCircusDemon 3 ปีที่แล้ว

      Damn, same, I clicked this in my recommended (I've always been horrible at math) I don't get how people in the comments get it so easily

  • @RizzY_RUS
    @RizzY_RUS 5 ปีที่แล้ว +20

    Drink game:
    Take a shot after he says the letter "i"

    • @skullzs1983
      @skullzs1983 6 หลายเดือนก่อน

      You'd get drunk after the first 10 seconds.

  • @anishpawar1893
    @anishpawar1893 3 ปีที่แล้ว +1

    alternate method:
    i^(1/i)=x
    i=x^i
    now we know e^(i . pi/2) =i
    therefore i=e^(i . pi/2) = x^i
    so, x=e^(pi/2)

  • @fountainovaphilosopher8112
    @fountainovaphilosopher8112 7 ปีที่แล้ว +182

    Who thinks new BPRP is more interesting and better? *raises hand*

    • @blackpenredpen
      @blackpenredpen  7 ปีที่แล้ว +8

      Ognjen Kovačević thank you!!!

    • @maxhaibara8828
      @maxhaibara8828 7 ปีที่แล้ว +3

      yay!!

    • @blackpenredpen
      @blackpenredpen  7 ปีที่แล้ว +12

      Ognjen Kovačević u know. It's weird that even tho I teach the same way in my classes. But I have been doing different things on YT nowadays and I have been enjoying it way more also.

    • @maxhaibara8828
      @maxhaibara8828 7 ปีที่แล้ว +4

      blackpenredpen wait you're a teacher?! I thought you're just a super smart student!!

  • @travishayes6037
    @travishayes6037 7 ปีที่แล้ว +184

    As mentioned before, I love this channel. Found it randomly, but so glad I did.
    Currently a grad student taking complex analysis (as an elective, took it 2years ago). All of your complex videos are just supplementary/review for me, but they're still very satisfying to watch.
    Got any plans for singularities?

    • @blackpenredpen
      @blackpenredpen  7 ปีที่แล้ว +19

      Travis Hayes great idea! I will discuss this with peyam bc we are filming together this Friday

    • @retired5548
      @retired5548 7 ปีที่แล้ว +4

      in a sense,all of his videos are complex

    • @retired5548
      @retired5548 7 ปีที่แล้ว +1

      in two,actually. at least two

    • @normanbraslow7902
      @normanbraslow7902 3 ปีที่แล้ว +1

      I don't believe a word of what you say! You doubtless are as flummoxed as the rest of us mortals. Quit showing off!

  • @Treegrower
    @Treegrower 7 ปีที่แล้ว +272

    You are a math god

  • @tracychacon1210
    @tracychacon1210 ปีที่แล้ว +2

    This video is amazing. Thank you for the break down!

  • @anirudhbhalekar
    @anirudhbhalekar 7 ปีที่แล้ว +18

    You're explanations are simple and crisp, really helping me learn mathematics better

  • @Jackthe_ripper-te3uw
    @Jackthe_ripper-te3uw 25 วันที่ผ่านมา

    i=e^i pi
    i'th root of i =( e^i pi/2) ^1/i= e^pi/2

  • @112BALAGE112
    @112BALAGE112 7 ปีที่แล้ว +1

    There are other solutions as well: (e^(pi/2+2*n*pi))^i = i for integers n.

  • @SoumilSahu
    @SoumilSahu 7 ปีที่แล้ว +61

    black mic red shirt yay!

  • @EdKolis
    @EdKolis ปีที่แล้ว +3

    Imagine if imaginary roots of other imaginary things could be real. Like trees.

  • @devjain2319
    @devjain2319 3 ปีที่แล้ว +7

    e, pi, and i: The Zeus Poseidon and Hades of math

  • @camerongray7767
    @camerongray7767 5 ปีที่แล้ว +14

    I don’t even know how to begin to do this

  • @GrowlyBear917
    @GrowlyBear917 3 ปีที่แล้ว +1

    I'm going to use this information when I file my taxes.

  • @dhyeypatel8399
    @dhyeypatel8399 7 ปีที่แล้ว +8

    That was the question that i had not been able to solve in my exam thanks

  • @AtariDays80
    @AtariDays80 3 ปีที่แล้ว +7

    I still find it odd that "i" with absolute magnitude of "1" can ever twist itself into something outside of that, as in > 1.

  • @kevinpaulsen6103
    @kevinpaulsen6103 5 ปีที่แล้ว

    I love it when blackpenredpen features blackpenredpen.

  • @dane1234abc1
    @dane1234abc1 3 ปีที่แล้ว

    You are the most brilliant math person I have ever come across. I am in awe.

  • @vedantchafle6038
    @vedantchafle6038 3 ปีที่แล้ว

    The whole point of the question was to explain that e term, and you bring that from within the thin air, solving the sums fast doesnt mean you miss the real part of the solution

    • @vedantchafle6038
      @vedantchafle6038 3 ปีที่แล้ว

      Tell them we wrote "i" as "e^i(theta)" and the "i" and "1/i" cancels out

  • @Vince0
    @Vince0 6 ปีที่แล้ว +3

    That ball that you always keep in your hand makes you look like an ood from DW xD

  • @billf7585
    @billf7585 3 ปีที่แล้ว +1

    You can check its true, if you raise both sides to the power i, you get i = e^(i*pi/2) which is the complex polar form of a vector with argument pi/2 and magnitude 1, which is of course just i on the complex plane. The family of solutions are associated with all arguments that equal pi/2 mod 2pi, so any integer number of times around the units circle landing back at i.

  • @samuelwillowcreek8764
    @samuelwillowcreek8764 4 ปีที่แล้ว

    That moment when you try to checkmate a grandmaster and he just literally flips the board. Great stuff man, I didn't this was a question that bothered me since 3 minutes ago but thanks for the answer anyways.

  • @paradox6647
    @paradox6647 ปีที่แล้ว

    Another way is to get this result is to convert i into it’s polar form, you get there a lot quicker

  • @coolpool7168
    @coolpool7168 5 ปีที่แล้ว +1

    (X^2-5x+5)^(x^2+7x+12)=1
    Find all real values of x.
    There will be 6 values of x.
    Love from India.

  • @mikeCavalle
    @mikeCavalle 3 ปีที่แล้ว +1

    nicely done.... the use of multi color to force focus reminds me of a math professor in the 1960's at the University of Maine.

  • @parthiban5663
    @parthiban5663 5 ปีที่แล้ว +1

    Your voice is a lullaby 😭❤️

  • @erikev
    @erikev ปีที่แล้ว +1

    And 5 years later: Just go straight for Eulers identity: i'th root of i = i^(1/i)=e^(πi/2i)=e^π/2 From 5 steps to 3 steps

  • @maddurihemant9157
    @maddurihemant9157 7 ปีที่แล้ว +1

    Sir there can also be my method:
    Let i^1/i=x
    Take ln both sides..
    Now 1/i×ln(i)=ln(x)-----(1)
    Now as we know e^iπ=-1
    And(-1)=i^2
    e^iπ=i^2 then take ln both sides then (iπ)=2ln(i)
    Which equals (iπ)/2=ln(i)------(2)
    Now put (2) in (1)=
    {ln (i)=iπ/2}
    1/i×iπ/2=ln(x)====
    π/2=ln(x) so
    e^π/2=x
    I hope this can also be a solution...☺

  • @japeking1
    @japeking1 7 ปีที่แล้ว

    These just make me so cheerful..... I have to limit myself to one a day ( and then I'll start again from the beginning because I'm still forgetting stuff like when I was a kid. )

  • @robert_wigh
    @robert_wigh 3 ปีที่แล้ว

    Why so complicated though?
    Q: i^(1/i)=?
    Solution
    Rewriting the BASE i on the polar form, by analyzing the complex plane we get that r=1 and θ=π/2+2n, n∈ℤ. Therefore, i=cos(π/2+2n)+isin(π/2+2n). By Euler's formula this can be written as i=e^(i(π/2+2n)).
    Keeping the EXPONENT on it's original form, we can conclude that
    i=(e^(i(π/2+2n)))^(1/i)=e^(π/2+2n) by simplification
    A: i^(1/i)=e^(π/2+2n)
    By plugging in n=0 we get the answer i^(1/i)=e^(π/2), as presented in this video.

  • @Ni999
    @Ni999 5 ปีที่แล้ว

    So much love given to -
    i = e^(iπ2(k+¼))
    - in all of its forms and so little given to -
    i = -e^(iπ2(k-¼))
    i^(1/i) = -e^(-π/2 + 2kπ) or e^(π/2 + 2kπ)
    You can't just add multiples of 2π to the positive result and declare victory.

  • @hamsack981
    @hamsack981 3 ปีที่แล้ว

    I don't even think about this kind of stuff. It's crazy that some dude was like, oh there's an i'th root of I, let's solve what it is...

  • @nosirrahx
    @nosirrahx 4 ปีที่แล้ว

    If I have learned anything from this channel it is that if you something strange to i, e and/or pi are going to pop out of the equation.

  • @meerable
    @meerable 2 ปีที่แล้ว

    As far as I know, the transition from sqrt to power imposes restrictions on the argument. And here it is observed?

  • @simonwillover4175
    @simonwillover4175 3 ปีที่แล้ว

    Well, _i_ root of _i_ is pretty easy to calculate.
    The _a_ root of _b_ can be rewritten as _a_ ^(1/ _b_ )
    So, _i_ root of _i_ = _i_ ^( 1/ _i_ )
    Now, 1/ _i_ = -i. You can figure that out geometrically / visually with ease.
    _a_ ^ ( - _b_ ) = 1 / ( _a_ ^ _b_ )
    So, _i_ root of _i_ = _i_ ^( 1/ _i_ ) = _i_ ^ (- _i_ ) = 1/ ( _i_ ^ _i_ )
    To calculate _i_ ^ _i_ , we can use one of euler's formulas. For starters, _a_ ^ _b_ = _e_ ^( ln( _a_ ) _b_ ), thus _i_ ^ _i_ = _e_ ^( ln( _i_ ) _i_ )
    ln( _a_ + _bi_ ) = ln( length( _a_ + _bi_ ) ) + angle( _a_ + _bi_ ) _i_ , so _e_ ^( ln( _i_ ) _i_ )
    = _e_ ^( ( ln( length( _i_ ) ) + angle( _i_ ) _i_ ) _i_ )
    = _e_ ^( ( ln( 1 ) + angle( _i_ ) _i_ ) _i_ )
    = _e_ ^( ( 0 + angle( _i_ ) _i_ ) _i_ )
    = _e_ ^( ( angle( _i_ ) _i_ ) _i_ )
    = _e_ ^( ( 1/2 _pi i_ ) _i_ )
    = _e_ ^( 1/2 _pi i i_ )
    = _e_ ^( -1/2 _pi_ ) becuase _i i_ = -1
    Now, _e_ ^( -1/2 _pi_ )
    All of that says _i_ ^ _i_ = _e_ ^( -1/2 _pi_ )
    We still have to find 1/that.
    1/( _a_ ) = _a_ ^(-1), so 1/( _e_ ^( -1/2 _pi_ ) ) = _e_ ^( -1/2 _pi_ ) ^(-1). Stacked exponents multiply, so _e_ ^( -1/2 _pi_ * -1 ). The negative cancel, resulting in:
    _i_ root of _i_ = _e_ ^( 1/2 _pi_ ). The last part here can be calculated.
    In conclusion, the _i_ root of _i_ = _e_ ^( 1/2 _pi_ ) ~~ 4.8105

    • @michielschaeverbeke1421
      @michielschaeverbeke1421 3 ปีที่แล้ว

      You say "1/ i = -i. You can figure that out geometrically / visually with ease." But I fail to see that visually... I only get that algebraically

  • @radward7173
    @radward7173 2 ปีที่แล้ว

    damn I didn't know about imaginary numbers more than how to write them and how to show them on complex plain. yet after watching several other videos of yours I managed to get this one by myself.

  • @hmafussel94
    @hmafussel94 4 ปีที่แล้ว +1

    is this really the right answer?
    look at this:
    i = exp(pi * i / 2) = exp(5* pi * i /2)
    but now the i-th root of it can be
    exp(pi / 2) or exp(5* pi /2) or any other power of the form (4n+1) * pi / 2

  • @thibautklinger5178
    @thibautklinger5178 3 ปีที่แล้ว

    When I saw the video I took a few minutes to think about it for myself and then come back to see if I was right and I was. Thanks I like keeping my mind sharp with little math riddles like this one.

  • @maxhaibara8828
    @maxhaibara8828 7 ปีที่แล้ว +36

    but the real question is... what is i-th root of i based on Wolfram Alpha?

    • @blackpenredpen
      @blackpenredpen  7 ปีที่แล้ว +10

      Max Haibara lol!!!!

    • @MattMcIrvin
      @MattMcIrvin 6 ปีที่แล้ว +4

      Just tried it... it says what he said

    • @Pacvalham
      @Pacvalham 5 ปีที่แล้ว +1

      I just did it before reading the comments, then I did e^(pi/2), then I compared the decimals, and they are the same, so W|A agrees.

    • @victorvega8061
      @victorvega8061 5 ปีที่แล้ว

      @@MattMcIrvin The joke is that you don't need Wolfram Alpha to solve seemingly difficult equations.

    • @snbeast9545
      @snbeast9545 4 ปีที่แล้ว

      Even calculators can compute it, and they give the same answer. (Done on a TI-84)

  • @TheMartnK
    @TheMartnK 6 ปีที่แล้ว +3

    You should probably also update this version with e^(pi/2+2*pi*n)

  • @Lily-zd6dx
    @Lily-zd6dx 6 ปีที่แล้ว +2

    "What we do now? We do our usual business" if math was that easyyy

  • @Uni-Coder
    @Uni-Coder 6 ปีที่แล้ว +1

    By the fundamental theorem of algebra, there are exactly n roots of nth power. So, there are exactly i roots of i :)

  • @danialbrown4417
    @danialbrown4417 4 ปีที่แล้ว

    Black pen blue pen would make it easier for my eyes to read. Thank you so much for your videos.

  • @HanzCastroyearsago
    @HanzCastroyearsago 2 ปีที่แล้ว

    “I dont like to be on the bottom, i like to be on the top”
    - pen guy

  • @theimmux3034
    @theimmux3034 4 ปีที่แล้ว

    Of cooourse, (e^(pi÷2))^i is just equal to e^(i(pi÷2)) which is i in polar form.

  • @MrOligi3003
    @MrOligi3003 5 ปีที่แล้ว

    The x-th root of x is at maximum at x=e for x a real number. e-th root of e is about 1.444... This tops it by 3.3...

  • @ianboard3555
    @ianboard3555 3 ปีที่แล้ว

    I've given this as an interview question (I'm an EE) - it's easy if you just work your way through it.

  • @martinhughes2637
    @martinhughes2637 3 ปีที่แล้ว

    This is so fantastic and beautiful. Thank you for sharing!!

  • @marcusrosales3344
    @marcusrosales3344 5 ปีที่แล้ว

    You could easily motivate this by analogy with a square root. Like square root of 4 can be found by finding a number a such that:
    a^2=4 ==>a=2.
    Similarly, the ith root of i means find an a such that:
    a^i=i ==> a=e^(pi/2)

  • @jherbranson
    @jherbranson 3 ปีที่แล้ว

    The fact that it ends up a real number is really weird for some reason.

  • @GlorfindelSnipes
    @GlorfindelSnipes ปีที่แล้ว

    " I don't like to be on the bottom, i like to be on the top " (0:31)
    - blackpenredpen 2017

  • @pythondrink
    @pythondrink 7 หลายเดือนก่อน

    0:30 "I don't like to be on the bottom. I like to be on the top."-Blackpenredpen, 2017

  • @philipyao5989
    @philipyao5989 7 ปีที่แล้ว +170

    Wait ur a teacher!?

    • @blackpenredpen
      @blackpenredpen  7 ปีที่แล้ว +71

      Philip Yao yes i am

    • @maxhaibara8828
      @maxhaibara8828 7 ปีที่แล้ว +52

      blackpenredpen you're so young that we thought you're a 20-years old math youtuber haha

    • @victorvega8061
      @victorvega8061 5 ปีที่แล้ว +2

      @@blackpenredpen where do you teach I have to go there (つ°ヮ°)つ

    • @hherrera007
      @hherrera007 5 ปีที่แล้ว +2

      Nop, he is a math god.

    • @sals4659
      @sals4659 5 ปีที่แล้ว +1

      @@victorvega8061 UC Berkeley

  • @ravipatiggkrishna8532
    @ravipatiggkrishna8532 3 ปีที่แล้ว

    The above i^(1/i) has many infinite solutions e^(-pi/2) is one of it

  • @czerbniak75
    @czerbniak75 3 ปีที่แล้ว

    Tak na dobry sen. U mnie luzik. Dobranoc, kurde jeszcze jasno.

  • @g_vost
    @g_vost 11 หลายเดือนก่อน

    such an interesting edge case!

  • @manda3dprojects966
    @manda3dprojects966 6 ปีที่แล้ว +1

    There are infinite solutions: e^(pi/2 + 2*pi*n)

  • @atomgutan8064
    @atomgutan8064 2 ปีที่แล้ว

    I just realized that to get from i^i to i^1/i you need to multiply the exponent by 1/i^2 and that is 1/-1 which is the same as - 1 so (i^i)^-1 = i^1/i then you can solve it like this: (i^i)^-1 = (e^(-pi/2))^-1 = e^(-1*-pi/2) = e^(pi/2)

  • @heathledger9939
    @heathledger9939 5 ปีที่แล้ว

    i = e^i(2n+1)π/2 So i^(1/i) = e^(2n+1)π/2 for any n as an integer

  • @ffggddss
    @ffggddss 7 ปีที่แล้ว +1

    Let's see, this is math, where we always try to answer a new problem by casting it into terms of one we've already solved . . .
    i-root of i = i^(1/i) = i^(-i) = 1/(i^i) and we've already visited i^i; it's = e^(-½π).
    So the (principal) i-root of i = e^(½π) ≈ 4.810477...

  • @flamingpaper7751
    @flamingpaper7751 7 ปีที่แล้ว +7

    What would an ith root(x)graph look like?

  • @async_RNN
    @async_RNN 5 ปีที่แล้ว +1

    _this just sounds like euler's formula with extra steps_

    • @Itstimetorecover
      @Itstimetorecover 5 ปีที่แล้ว

      It used Euler’s formula at the end to compute it
      i=e^(i*pi/2)
      raise both sides to the power of i and you get
      i^i=e^(-pi/2)

  • @pfeffer1729
    @pfeffer1729 7 ปีที่แล้ว +19

    Could also just write e^(pi i/2) = i and take the root of both sides.

    • @obinnanwakwue5735
      @obinnanwakwue5735 7 ปีที่แล้ว

      Ian But that requires you to know sqrt(i).

    • @pfeffer1729
      @pfeffer1729 7 ปีที่แล้ว +5

      Obinna Nwakwue I meant the i-th root.
      You have i = e^(pi i/2)
      rt_i (i) = rt_i ((e^(pi/2)^i) = e^(pi/2)

    • @ello-m8
      @ello-m8 7 ปีที่แล้ว +5

      Ian That's exactly what I thought of once I saw the last step.
      This way is much simpler.

    • @ApplepieFTW
      @ApplepieFTW 7 ปีที่แล้ว

      Ian but that would require you know that e^(pi i/2) is equal to -minus one- i, and how do you know that? tho I guess here you have to know what i^i is so not really that much of a difference

    • @pfeffer1729
      @pfeffer1729 7 ปีที่แล้ว +3

      ApplepieFTW actually e^(pi i/2) = i, but I catch your point. The problem is that roots and noninteger powers are defined in terms of the exponential function on C, so...

  • @intekhabalam2027
    @intekhabalam2027 3 ปีที่แล้ว

    Math is becoming a celebration for u people. Lots of love and respect from me.

  • @jw-ws8dz
    @jw-ws8dz 5 ปีที่แล้ว

    While verifying the solution to this (and to i^i), I encountered a paradox:
    Since i^i and i^(1/i) are reciprocals of each other, they should multiply to be equal to one.
    i^i*i^(1/i)=e^(-pi/2)*e^(pi/2)=1
    However, if I evaluate i^i*i^(1/i) a different way, I get a different answer.
    i^i*i^(1/i) = i^(i+1/i)=i^((i+1)/i)=i^((-1+i)/-1)=i^(1-i)
    Using exponent rules, we can rewrite i^(1-i) as i*i^(-i)=i/(i^i)
    We have already calculated that i^i=e^(-pi/2), so we can substitute this into the original equation
    i/(i^i)=1
    i/e^(-pi/2)=1
    i*e^(pi/2)=1
    The math used to evaluate i^i in the first place is clearly right, so I don't know what the problem is. How can a real number somehow be equal to an imaginary number?

    • @jw-ws8dz
      @jw-ws8dz 5 ปีที่แล้ว

      I just checked wolfram alpha btw, and it says 1, so I'm assuming that math isn't broken. However, I am also strongly convinced that the alternative approach I took to evaluating i^i*i^(1/i) is also correct.

  • @NardiPaffon
    @NardiPaffon 3 ปีที่แล้ว

    "Let me do a REAL quick video for you" I see what you did there

  • @Саня-я4х6в
    @Саня-я4х6в 18 วันที่ผ่านมา

    So this right here actually makes A LOT OF SENSE , if we build a graph of nth root of n , it peaks at e-th root of e , and i-th root of i is 4.81 that should be possible but this is imaginary so that's why we get a real numbers like that

  • @cleiven3533
    @cleiven3533 5 ปีที่แล้ว +2

    Could one also write i^(1/i) as (e^(pi/2)i)^(1/i), because e^(pi/2) = i according to Euler's formula, allow the i and 1/i to cancel out, and take the remaining e^(pi/2) as a final answer?

  • @NaradaFox
    @NaradaFox ปีที่แล้ว

    I accidentally created a generalized formula for the i-th root of any complex number with a radius of 1 in school which consists of i-th root(z) = e^a, a is equal to the angle of the complex number in polar form.
    The first version of my formula is the i-th root(z) = i-th root(r) • i-th root(e^(i•a)), a is still the angle of the number in polar form (only works with the radius of 1).

    • @NaradaFox
      @NaradaFox ปีที่แล้ว

      Also, I removed the i-th root of r from the first version simply because it is useless since it is the i-th root of a number, where the i-th root is not defined. So r must be equal to 1 and the i-th root of 1 must be equal to 1.

  • @mackthisarrowhearth295
    @mackthisarrowhearth295 5 ปีที่แล้ว +1

    Doesn't this give a problem? i=e^(pi/2+2 k pi)i for any integer k, thus we obtain e^(pi/2)*e^(2 k pi) for any integer k, thus we obtain a lot of different values?

  • @clmbyl3717
    @clmbyl3717 4 ปีที่แล้ว

    A lot easear with the exponential formula, i^(1/i) = (e^i(pie/2))^(1/i)

  • @ijarbis187
    @ijarbis187 5 ปีที่แล้ว

    I just thought of it as (e^(i*pi/2))^(1/i) then the i’s cancel out and boom e^(pi/2) this is only 1 step and a little easier

  • @NoName-jh7yj
    @NoName-jh7yj 3 ปีที่แล้ว

    Using e^πi = -1, you can realize that i = √(-1) = √(e^πi) = e^(π/2)i
    Now i^(1/i) is obviously equal to (e^(π/2)i/i), which is equal to e^(π/2).

  • @p1xelat3d
    @p1xelat3d 8 หลายเดือนก่อน

    0:30 the quote of all time

  • @Sma.Das.
    @Sma.Das. 7 ปีที่แล้ว

    Considering that on a Cartesian plane moving by pi is 180° so since it is pi/2 which is 90° therefore you can have the statement pi*(4n-3)/2 where n is any real number ;)

  • @_DD_15
    @_DD_15 6 ปีที่แล้ว +1

    Why did you multiply by i over i? You could have substituted e to the i pi/2 as first step. And then cancel out the i and get the result in 2 steps. :)

  • @renangustavo3844
    @renangustavo3844 5 ปีที่แล้ว

    Omg, u did it so easily. The way that I've done was making:
    Y=i^(1/i)
    ln(Y)=ln(i)/i
    then, i = e^(iπ/2)
    ln(Y)=ln(e)×iπ/2i
    ln(Y)=π/2
    Y=e^(π/2)

  • @Fredson167
    @Fredson167 5 ปีที่แล้ว +10

    00:32 Lost my concentration there

  • @Pining_for_the_fjords
    @Pining_for_the_fjords 6 ปีที่แล้ว +1

    The very concept of an ith root doesn't make sense to me.

  • @nabeelkhan4910
    @nabeelkhan4910 6 ปีที่แล้ว

    Natural log of (i) is equal to pi by 2 times i
    tk i to lhs and tk it to power of the index and then raise it to the power of e