Proof $\mathbb{Z}[i]/(2- i) \cong \mathbb{Z_5}$
120594
$\mathbb Z[i]/ \langle 1+2i \rangle \cong \mathbb Z_5$
93169
Show that $(\mathbb Z[x],+)$ and $(\mathbb Q_{>0},\cdot)$ are isomorphic groups
138058
Prove that $\mathbb Z_{m}\times\mathbb Z_{n} \cong \mathbb Z_{mn}$ implies $\gcd(m,n)=1$.
65558
Irreducible in $\mathbb{Z}[\sqrt{-5}]$
70522
$y^2 = \frac{x^5 - 1}{x-1}$ & $x,y \in \mathbb{Z}$
33781
Is $\mathbb{Z}[x]/(x^2+1)$ isomorphic to $\mathbb{Z}[i]$?
76100
Showing that $\left\langle a,b \mid abab^{-1}\right\rangle \cong \pi_1(K) \cong \left\langle c,d \mid c^2 d^2 \right\rangle$
8977
Showing $x^{5}-ax-1\in\mathbb{Z}[x]$ is irreducible
119832
Galois group of the splitting field of the polynomial $x^5 - 2$ over $\mathbb Q$
67772
How to find $k$ such that $(\mathbb{Z} \times \mathbb{Z})/ \langle (m,n)\rangle \cong \mathbb{Z} \times \mathbb{Z}_k$
4648
Proving that $\mathbb{Z}_m\oplus \mathbb{Z}_n \cong \mathbb{Z}_d\oplus \mathbb{Z}_l $ as groups, where $l=\mathrm{lcm}(m,n)$ and $d=\gcd(m,n)$
90433
Isomorphisms between $(\mathbb Z_4,+)$ and $(U_5,*)$
59134
Proving idempotent elements in $\mathbb{Z}_n$
19310
Identify the ring $\mathbb{Z}[x]/(2x)$
121280
Proving that $a \mathbb{Z} \cap b\mathbb{Z} = \operatorname{lcm}(a,b)\mathbb Z$
87160
Prove $\mathbb{Z}_3[x]/(x^2+1)$ and $\mathbb{Z}_3[x]/(x^2+x-1)$ are isomorphic.
122581
Prove or disprove that $G_1/H_1 \cong G_2/H_2$