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A song about a circle constant

Happy Tau Day! This is a song about Tau! Other Tau things you should see:Pi is (still) Wrong: http://youtu.be/jG7vhMMXagQ What Tau Sounds Like: http://youtu.be/3174T-3-59QThe Tau Manifesto: http://tauday.com/. Created by Vi Hart.

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  • male robot hal style avatar for user Paul Giessner
    Did anyone else notice that when Vi was singing the digits of tau, the higher the digit of tau, the higher the note she sang was? (except 0 which was the highest)
    (466 votes)
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  • aqualine sapling style avatar for user Emma W.
    6.
    2831853071 7958647692 5286766559 0057683943 3879875021
    1641949889 1846156328 1257241799 7256069650 6842341359
    6429617302 6564613294 1876892191 0116446345 0718816256
    9622349005 6820540387 7042211119 2892458979 0986076392
    8857621951 3318668922 5695129646 7573566330 5424038182
    9129713384 6920697220 9086532964 2678721452 0498282547
    4491740132 1263117634 9763041841 9256585081 8343072873
    5785180720 0226610610 9764093304 2768293903 8830232188
    6611454073 1519183906 1843722347 6386522358 6210237096
    1489247599 2549913470 3771505449 7824558763 6602389825
    9667346724 8813132861 7204278989 2790449474 3814043597
    2188740554 1078434352 5863535047 6934963693 5338810264
    0011362542 9052712165 5571542685 5155792183 4727435744
    2936881802 4499068602 9309917074 2101584559 3785178470
    8403991222 4258043921 7280688363 1962725954 9542619921
    0374144226 9999999674 5956099902 1194634656 3219263719
    0048918910 6938166052 8504461650 6689370070 5238623763
    4202000627 5677505773 1750664167 6284123435 5338294607
    1965069808 5751093746 2319125727 7647075751 8750391556
    3715561064 3424536132 2600385575 3222391818 4328403978
    7619051440 2130971726 5577318723 0676365593 6460603904
    0706037059 3799154724 5198827782 4994435505 6695826303
    1149714484 9083013919 0165906623 3723455711 7781501967
    6350927492 9878638510 1208018554 0334227801 9697648025
    7167232071 2741532020 9420363885 9111923978 9353567489
    8896510759 5494536942 0809506929 2416093368 5181389825
    8662735405 7978304209 5043241139 3204811607 6300387022
    5067648600 7117528049 4992946527 8283985452 0853984559
    3564709563 2720186834 4328243984 9172630060 5723659491
    1141349967 7010989177 1738539913 8185442159 5018605910
    (15 votes)
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  • starky ultimate style avatar for user austin ungerman
    So is the circumference of a circle Tau*radius?
    (12 votes)
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  • piceratops ultimate style avatar for user Saifa
    i also wonder how she got to make her own videos on KhanAcademy!
    (3 votes)
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  • hopper cool style avatar for user Chubtato
    at what is a 4 dimensional object
    (2 votes)
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  • hopper cool style avatar for user Hannah
    She has a very unique voice don't you think!
    (3 votes)
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  • orange juice squid orange style avatar for user Tyler  Tutt
    Isn't Tau basically Pi times 2?
    (3 votes)
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  • aqualine ultimate style avatar for user Thomas Bailey
    So does this mean what I learned in elementary school is wrong and my 6th grade math teacher celebrated pi day for no reason?(T-I)
    (3 votes)
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  • female robot grace style avatar for user nebulagirl
    Is Vi the one playing the guitar?
    (3 votes)
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  • aqualine ultimate style avatar for user Eric
    At , why did she start singing about tau? Tau is just
    3.141592653589793... x 2
    = 6.28318530717958647692528676655900576839433875021.....
    Tau is just pi + pi or pi times 2.
    (I got the whole thing from Vi)
    And the notes... they are higher the higher the digit is. 0 is the highest.
    WHY?
    (3 votes)
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Video transcript

(SINGING) When you want to make a circle, how is it done? Well, you probably will start with the radius 1. Then use a compass or a string, and use a paper or the ground. And if the radius is 1, how far did you go around? It's tau, 6.28. Yeah, it's tau, 6.28318530717958. If you pick a certain distance, and you pick a certain spot, and you put the two together, then what have you got? It makes a very special shape, and now you are the inventor, if you take all of the points a certain distance from your center. And you've got a great collection, and it is a great invention. And it makes a lovely circle, well, depending on dimension. Because it's 1, 2, 3, then there's 4 and even more. But for a circle, how much circle's there if you take the distance and compare? It's tau, 6.28. Yeah, it's tau, 6.28318530717958647692528. I know what you are thinking, what about that other guy? The one that's sometimes pronounced pee, and it's sometimes pronounced pi? I mean, it's fine if you are building, but does not belong in math. All the equations make more sense when you use taw or you use taff. Well, you get the same answers no matter which way. We get further from truth when we obscure what we say. You know that math makes sense when it's beautiful and pure. So please don't make it ugly with your bad notation and awful curriculum. Use tau, 6.28. Yeah, use tau, 6.28318530717958647692528676655900576839338750211.