MHB Understanding Bland's Proof of Proposition 4.3.14: Primitive Elements of Modules

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I am reading Paul E. Bland's book, "Rings and Their Modules".

I am focused on Section 4.3: Modules Over Principal Ideal Domains ... and I need yet further help in order to fully understand the proof of Proposition 4.3.14 ... ...

Proposition 4.3.14 reads as follows:

View attachment 8326
View attachment 8327
In the above proof by Bland we read the following:

" ... ...If $$y \neq 0$$, then we can write $$y = y' b$$ where $$y'$$ is a primitive element of $$F$$ and $$b$$ is a nonzero element of $$R$$ ... ... "Can someone explain why/how it is that we can write $$y = y' b$$ where $$y'$$ is a primitive element of $$F$$ and $$b$$ is a nonzero element of $$R$$ ... ... Help will be much appreciated ... ...

Peter==========================================================================================

It may help MHB

members reading this post to have access to Bland's definition of 'primitive element of a module' ... especially as it seems to me that the definition is a bit unusual ... so I am providing the same as follows:View attachment 8328Hope that helps ...

Peter
 
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This is a direct consequence of lemma 4.3.10 on page 123.
 
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