(New page: Show that Phi_n(x) is reducible if n is not prime.)
 
 
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Show that Phi_n(x) is reducible if n is not prime.
 
Show that Phi_n(x) is reducible if n is not prime.
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For this one I modified the corollary for Eisenstein's Criterion to show that n divides all of the coefficients.
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I used Eisenstein's Criterion with n=p^2, so that n is composite. So p divides all coefficients, and p^2 divides the last coefficient. This implies polynomial is reducible when p is not prime.
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-Ozgur

Latest revision as of 08:54, 16 November 2008

Show that Phi_n(x) is reducible if n is not prime.


For this one I modified the corollary for Eisenstein's Criterion to show that n divides all of the coefficients.


I used Eisenstein's Criterion with n=p^2, so that n is composite. So p divides all coefficients, and p^2 divides the last coefficient. This implies polynomial is reducible when p is not prime.

-Ozgur

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