If $[a],[b] \in \mathbb{Z}_n^* $ then $[ab] \in \mathbb{Z}_n^*$: a doubt about equivalence classes.
39563
How to show $a,b$ coprime to $n\Rightarrow ab$ coprime to $n$?
150064
Cardinality of "$x-y\in\Bbb Q$"-equivalence class of $1/\sqrt2$
62474
If $AB=I_n$ and $BA=I_m$ then $n=m$.
141961
What is the difference between [[ $a == z* ]] and [ $a == z* ]?
18018
Proving that $4 \mid m - n$ is an equivalence relation on $\mathbb{Z}$
46780
Proving $((a\bmod n) (b\bmod n))\bmod n = ab\bmod n $
14003
$(\mathbb{Z}/2^n \mathbb{Z})^*$ is not cyclic Group for $n\geq 3$
40321
$\operatorname{Aut}(\mathbb Z_n)$ is isomorphic to $U_n$.
26661
Ring homomorphisms from $\mathbb{Z}_n$ to $\mathbb{Z}_m$
17978
Isomorphism classes of $\mathbb{Z}[i]$ modules.
89190
Why is it true that $|AB:A|=|B:A\cap B|$ even if $A$ is not normal in $AB$? (Second Isomorphism Theorem)
155745
Ideals of $\mathbb{Z}[X]$
83938
If$(ab)^n=a^nb^n$ & $(|G|, n(n-1))=1$ then $G$ is abelian
92703
Proving that $\mathbb{Z}[x]$ and $\mathbb{Q}[x]$ are not isomorphic.
78118
Algebraically, why is $\mathbb{Z}[i]/(i + 1)$ isomorphic to $\mathbb{Z}_{2}$?
105180
When does $(ab)^n = a^n b^n$ imply a group is abelian?
92211
When are $\mathbb Z_m$ and $\mathbb Z_n$ homomorphic?