Studies in Rings generalised Unique Factorisation Rings
Studies in Rings generalised Unique Factorisation Rings
Studies in Rings generalised Unique Factorisation Rings
Create successful ePaper yourself
Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.
-6-<br />
If both conditions hold, R is said to be<br />
Noetherian.<br />
Example 1 0 6 .<br />
It is easy to observe that the 2 x 2 matrices of<br />
the form [~~<br />
where a € Z and b,c E. Q make a r<strong>in</strong>g which<br />
) 1<br />
is right Noethcrian but not left Noetherian.<br />
Proposition 1 07.<br />
Let B be a submodule of A. Then A is Noetherian if<br />
and<br />
only if 8 and A/S are both Noetherian.<br />
Corollary 1.8.<br />
Noetherian.<br />
Any f<strong>in</strong>ite direct sum of Noetherian modules is<br />
Corollary 1.9.<br />
If R is a Noetherian r<strong>in</strong>g, all f<strong>in</strong>itely generated<br />
right R-modules are Noetheriano<br />
Def<strong>in</strong>ition 1010.<br />
Given a r<strong>in</strong>g R and a positive <strong>in</strong>teger n, we use<br />
M (R) to denote the r<strong>in</strong>g of all n x n matrices over R.<br />
n<br />
The standard n x n matrix units <strong>in</strong> M (R) are the matrices<br />
n<br />
e .. (for i,j = 1,2, •.. ,n) such that e .. has 1 as the i_jth<br />
1) 1J<br />
entry and 0 elsewhere.