Show that modules are isomorphic
69384
Are the following modules free and/or isomorphic?
108955
Showing $(\mathbb{Q},+)$ is not isomorphic to $(\mathbb{R},+)$
114773
counterexamples on modules
40321
$\operatorname{Aut}(\mathbb Z_n)$ is isomorphic to $U_n$.
114916
$\mathbb Z_{mn}$ isomorphic to $\mathbb Z_m\times\mathbb Z_n$ whenever $m$ and $n$ are coprime
137011
showing $\psi: R\to \mathbb C$ is ring isomorphism.
148828
Submodule of a free module
87397
Show that $a^2 \bmod b = (a \bmod b)^2 \bmod b$
50114
A question about direct sums and products of modules
113413
How do I show that two groups are not isomorphic?
57166
Showing that $\Bbb R[x] / \langle x^2 + 1 \rangle$ is isomorphic to $\Bbb C$ question
136422
Two finite fields with the same number of elements are isomorphic
86748
Isomorphism of hom sets implies objects are isomorphic
93176
Projectivity of a module
140865
Rings' second isomorphism theorem
61491
Complex Ring Isomorphism
1686
Show that quotient rings are not isomorphic