For commutative rings this definition is equivalent to the one given in the previous section.
For general commutative rings, we don't have a field of fractions.
The rational, real and complex numbers form commutative rings (in fact, they are even fields).
Let G be a group and A a commutative ring.
For commutative rings, all three concepts coincide, but in general they are different.
A commutative ring where the set with multiplication is a group.
If R is a commutative ring, then the above three notions are all the same.
Connections on a module over a commutative ring always exist.
In general, such functions will form a commutative ring.
This is the standard definition of the resultant over a commutative ring.