Solution: Let $m \in M$. Consider the set $Rm = {rm \mid r \in R}$. This is a submodule of $M$, and $M$ is a direct sum of these submodules.
Solution: Let $m \in M$. Consider the set $Rm = {rm \mid r \in R}$. This is a submodule of $M$, and $M$ is a direct sum of these submodules.
Solution: Let $m \in M$. Consider the set $Rm = {rm \mid r \in R}$. This is a submodule of $M$, and $M$ is a direct sum of these submodules.