Y by
For every integer
, let
be the set of all positive integers not exceeding
that are relatively prime to
. Consider the polynomial
![\[
P_n(x) = \sum_{k \in S_n} x^{k - 1}
\]](//latex.artofproblemsolving.com/3/a/c/3ac60cb70baf4dfcf297e9af87480a8ee34ba70c.png)
a) Prove that there exists a positive integer
and a polynomial
with integer coefficients such that
![\[
P_n(x) = (x^{r_n} + 1) Q_n(x).
\]](//latex.artofproblemsolving.com/7/0/e/70e19a9d3e0a7e97abc7aa08d3f23126c14ea7d0.png)
b)Find all integers
such that
is irreducible in
.




![\[
P_n(x) = \sum_{k \in S_n} x^{k - 1}
\]](http://latex.artofproblemsolving.com/3/a/c/3ac60cb70baf4dfcf297e9af87480a8ee34ba70c.png)
a) Prove that there exists a positive integer


![\[
P_n(x) = (x^{r_n} + 1) Q_n(x).
\]](http://latex.artofproblemsolving.com/7/0/e/70e19a9d3e0a7e97abc7aa08d3f23126c14ea7d0.png)
b)Find all integers


![$\mathbb{Z}[x]$](http://latex.artofproblemsolving.com/4/b/7/4b7d768fffbb7a1a6163af392ed348f2d49d8783.png)
This post has been edited 2 times. Last edited by luutrongphuc, Apr 5, 2025, 8:27 AM