|
|
Viewing Message
|
|
|
| ``Subring criterion''
by pahio on 2004-06-16 17:44:11 |
|
| The subset S of Z[X] which consists of polynomials with positive constant term is closed under addition and multiplication, but S is not subring of Z[X].
The sufficient (and necessary) subring criterion is that the non-empty S is closed under subtraction and multiplication. |
| | [ reply | up ] | |
|
|
|
|
|
|
|