Preface: This question is a result of personal interest, and has(adsbygoogle = window.adsbygoogle || []).push({}); nothingto do with any assignment.

Okay here's the deal; I've tutored trig in the past, and I've noticed one thing that a lot of folks have trouble with is the fact that there aretwopi radians per circle. (It doesn't help that pi can't help but remind most of us of a deliciously full pie.)

Anyway, that got me thinking: whyareradians defined such that two pi fits in each pie? We could easily redefine radians such that pi = pie, which is much more intuitive. (Don't believe me? Radian angle = S/2R. It works.)

So I'm hoping someone here is a math history buff, and can give me an answer. It'll probably be "Well this is how the first guy did it, so that's how we do it too," but I can hope for a more interesting answer.

Thanks in advance. :)

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# Rhyme and Reason Behind Radians?

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