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Current time:0:00Total duration:3:49

(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.