coequalizer of modules
1. Proposition
2. Proof
note that is a module homomorphism (see: Set of module homomorphisms as abelian group)
Hence the module
is a welldefined module
2.1. commuting
Let such that
.
Then
2.2. universal property
Let be another module and
making this a cofork Then it follows, that
or
Thus and by fundamental theorem of module homomorphisms, there exists a unique morphism