Area of a Circle

$$\text{Tau Day}$$

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Today (June $28$) is Tau Day!

What is tau? Tau, $\tau$, is a new constant that's attempting to replace $\pi$. Whereas $\pi$ is the ratio of a circle's circumference to its diameter, $\tau$ is the ratio of the circumference to its radius. Because of this, $\tau=2\pi=6.2831...$.

There is some good reasoning as to why $\tau$ could be the better choice. It does make a lot of equations and formulas look prettier. So spend this day appreciating $\tau$, even if you like $\pi$ more.