Adjoin inverse element to $\mathbb{Z}/12\mathbb{Z}$
32278
Adjoining 1/2 to $\Bbb{Z}/12\Bbb{Z}$
127664
Inverse elements in the absence of identities/associativity.
122312
How can I compute $\mathrm{Aut}(\mathbb{Z}/4\mathbb{Z}\times\mathbb{Z}/6\mathbb{Z})$?
87289
Find the multiplicative inverses of all the elements in $\Bbb Z_{16}^\times$
41035
Mapping that proves $\mathbb{Z} \subset \mathbb{Q}$
35714
Adjoint pairs, triplets and quadruplets
39788
$a+1,a-1$ invertible for nilpotent element
152306
Finding homomorphisms from $\mathbb Z_{12}$ to $\mathbb Z_{6}$.
108550
Elements of $\mathbb Q(2^{1/3})$
6837
How to quotient $\mathbb Z [\sqrt{-11}] / (1+\sqrt{-11})$?
43683
Finding Inverse of 2 (mod m)
1576
Finding the elements in the group of units of the ring of integers modulo n that are their own inverse.
102721
Number of elements in the ring $\mathbb Z [i]/\langle 2+2i\rangle$
75970
$\mathbb Z[1/2]$ is not finitely generated?
64419
How to construct a homomorphism from an abelian group to $\mathbb{Q}/\mathbb{Z}$?
6984
Inverting $a+b\sqrt{2}$ in the field $\Bbb Q(\sqrt{2})$
60212
algebraic element over a field