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THE  CORUNDUMINIUM

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MINIMAL  POLYNOMIALS  FOR  TRIG  FUNCTIONS

OF ANGLES  RATIONALLY  COMMENSURATE  WITH  π

 

 
  Announcement June 27, 2011:  The problem of generating these polynomials using elementary (precalculus) polynomial operations has been solved.  An addendum, completing the solution, will be published soon.  
           These are my latest notes (June 5, 2009) on the computation of minimal polynomials of all six trig functions of angles which are rational multiples of π.  We  now have elementary (precalculus) methods for computing them, but the proofs the process works are not elementary; relying for example on the irreducibility of the cyclotomic polynomials which requires an excursion into quotient fields for justification. 

     I have scanned the pages and thumbnailed them here.   Click on the thumbnails to get full images.  The manuscript has fourteen pages, and more will be added if we complete the association of tangents of classes divisible by 4 with their minimal polynomials.  You may print and disseminate these results without restriction.  If you have questions, please email me at williamh@wcjc.edu, and I will try to answer them for you.

     I am indebted to Jack Calcut of Michigan State University for his assistance and references to his own seminal work related to this problem. 

 
      
  Since scanning these pages, I have found some errata.

1:  The definition of an algebraic number on page 1 is incorrect.  The polynomial should have coefficients in Z or Q (real integers or rational numbers).