ABOUT THE MINIMAL POLYNOMIAL OF $\cos\frac{2\pi}{n}$

 

           We will not start any personal exposure without considering what is said in WIKIPEDIA.

           While reading about Chebysev polynomials,  the following article caught my eye:

Watkins, W. and Zeitlin, J. "The Minimal Polynomial of ." Amer. Math. Monthly 100, 471-474, 1993. 

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