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### Course: Math for fun and glory>Unit 1

Lesson 4: About pi and tau

# 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.

## Want to join the conversation?

• 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)
• That was the point. The notes correspond to the value of the digit. Kinda cool to hear how the numbers translate into music.
• 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
• Wow. That would have taken a while to type. Great Job!
• So is the circumference of a circle Tau*radius?
• Pi is circumference divided by diameter. That's why diameter multiplied by Pi equals circumference. Tau is circumference divided by radius.
• i also wonder how she got to make her own videos on KhanAcademy!
• Vi started her own math videos on YouTube. Her fame is quickly spreading, and of course, Sal, being a cool guy, found out about her, and probably asked her directly to feature her videos here!
• at what is a 4 dimensional object
• Actually, Steven Hawking has speculated that all objects have 4-dimensions, and the fourth dimension is time. Like, as an object grows older, the volume (or whatever you'd call it) of it's fourth dimension would increase.
• About Pi and Tau's description is the start of this song "When you want to make a circle, how is it done? Well you probably will start with the radius one." Lol who noticed
• I did notice "When you want to make a circle, how is it done? Well you probably will start with the radius one."
(1 vote)
• She has a very unique voice don't you think!
• Yep, it sounds a lot like her speaking voice in other videos.
• Isn't Tau basically Pi times 2?
• Tau is exactly Pi times 2. That is a logical consequence of their definitions.