# Revision history [back]

### Evaluating discriminant of a polynomial in Z_n[x]/<x^r-1>

Consider the following code

Zn=Zmod(n)
R = PolynomialRing(Zn,'x')
F = R.quotient((x**r)-1)
y=F((x+1))
f=F(y**n)


Clearly f will be a polynomial in xbar , I want to consider this polynomial as a polynomial in $\mathbb{Z}[x]$ and evaluate its discriminant.

I tried "f.polynomial()" but it is not working. Any suggestions ?

### Evaluating discriminant of a polynomial in Z_n[x]/<x^r-1>

Consider the following code

Zn=Zmod(n)
R = PolynomialRing(Zn,'x')
F = R.quotient((x**r)-1)
y=F((x+1))
f=F(y**n)


Clearly f will be a polynomial in xbar , I want to consider this polynomial as a polynomial in $\mathbb{Z}[x]$ and evaluate its discriminant.

I tried "f.polynomial()" "f.polynomial()" but it is not working. Any suggestions ?