Units in $\mathbb{Z} [\text{some root of unity}]$
47186
$(1-\zeta_m)$ is a unit in $\mathbb{Z}[\zeta_m]$ if m contains at least two prime factors
10589
How to factorize $5$ in $\mathbb{Z}[\root 3 \of 2]$?
39492
Finding $z\in \mathbb C$ with $\sin z = 2$?
52966
Rings, ideals and units-proof
68458
Roots of unity and large expression
99715
Proper ideal and units proof
155745
Ideals of $\mathbb{Z}[X]$
116360
Sum of n-th roots of unity
53661
Intuition surrounding units in $R[x]$
8434
Order of $\mathbb{Z}[i]/(1+i)$
133019
Nilpotent elements in $\mathbb Z_n$
87946
Proving that the unities of a ring form a group under multiplication
110416
Sums of roots of unity
31977
How to prove sum of powers property of roots of unity?
122932
When $(\mathbb{Q}(\zeta_n) : \mathbb{Q}) = 2$?
134342
Find a polynomial of degree > 0 in $\mathbb Z_4[X]$ that is a unit.
146980
Zero divisors of $\mathbb{Z}×\mathbb{Z}×\mathbb{Z}$