# Happy Pi Day! π Suuuper Celebraτion! -- Happy Tau Day! 6.28

#62

No it isn't..... this is a pi topic

#63

I'm reviving this topic because.. 6/28 is Tau Day!

Tau is exactly 2*pi
This is important because a circle is 2*pi Radians, or better yet, Tau Radians.

Engineers use Tau because it's more efficient to say half a circle is Tau/2 instead of Pi/4

#64

well, its also because the if the radius is 2 it will equal 6.283185307... and so on

#65

Interesting! I've never heard of Tau before. Does it have a symbol?

#66

It looks like this τ (Just like pi is a letter in the Greek alphabet, tau is also a letter in the Greek alphabet)

#67

Oooh and I have heard if we used tau instead of pi for Euler's identity, we'd get:

e = 1 (I think.. wait let me check)

#68

e^(i * pi) = -1
Euler's amazing special formula!

Oh, I've never hear dog the other one with Tau! I'll look it up!

I check Wolfram Alpha and it came up with some interesting Calculus derivative I do not understand yet. Doing more research

Absolute value of (e ^ ( i * Pi) ) = 1

Edit! You were right! Worlram thought that the Tau symbol was a variable for unknown reasons.. Wow! That's really awesome!

So when you multiply "pi" by even numbers, the result of the equation is "1"
With odd numbers, the result is "-1"
This is because of the cool trigonomic circle rotation it makes.. and I'm learning this next year! Yes!