Hom functor
= Hom functor
{title2=$\operatorname{Hom}_R(-,-)$}
{wiki}
The Hom functor sends two $R$-modules to the abelian group of $R$-linear maps between them. It is contravariant in its first argument and covariant in its second.
= Hom functor
{title2=$\operatorname{Hom}_R(-,-)$}
{wiki}
The Hom functor sends two $R$-modules to the abelian group of $R$-linear maps between them. It is contravariant in its first argument and covariant in its second.