Question 1173493
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*[tex \LARGE \pi] radians *[tex \LARGE = 180^\circ]


*[tex \LARGE \tan\varphi\ =\ \frac{\sin\varphi}{\cos\varphi}]


*[tex \LARGE \cot\varphi\ =\ \frac{1}{\tan\varphi}\ =\ \frac{\cos\varphi}{\sin\varphi}]


*[illustration Unit_Circle.jpg].
																
John
*[tex \LARGE e^{i\pi}\ +\ 1\ =\ 0]
My calculator said it, I believe it, that settles it
*[illustration darwinfish.jpg]

From <https://www.algebra.com/cgi-bin/upload-illustration.mpl> 
I > Ø
*[tex \Large \ \
*[tex \LARGE \ \ \ \ \ \ \ \ \ \  
								
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