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I am reading Paul E. Bland's book: Rings and Their Modules and am currently focused on Section 2.1 Direct Products and Direct Sums ... ...
I need help with another aspect of the proof of Proposition 2.1.1 ...
Proposition 2.1.1 and its proof read as follows:
In the above proof by Paul Bland we read the following:
" ... ... suppose that ##g \ : \ N \rightarrow \prod_\Delta M_\alpha## is also an ##R##-linear mapping such that ##\pi_\alpha g = f_\alpha## for each ##\alpha \in \Delta##. If ##g(x) = ( x_\alpha )## ... ... "When Bland puts ##g(x) = ( x_\alpha )## he seems to be specifying a particular ##g## and then proves ##f = g## ... ... I thought he was proving that for any ##g## such that ##\pi_\alpha g = f_\alpha## we have ##f = g## ... can someone please clarify ... ?Help will be much appreciated ... ...Peter
======================================================================================The above post mentions but does not define ##f## ... Bland's definition of ##f## is as follows:
Hope that helps ...
Peter
I need help with another aspect of the proof of Proposition 2.1.1 ...
Proposition 2.1.1 and its proof read as follows:
" ... ... suppose that ##g \ : \ N \rightarrow \prod_\Delta M_\alpha## is also an ##R##-linear mapping such that ##\pi_\alpha g = f_\alpha## for each ##\alpha \in \Delta##. If ##g(x) = ( x_\alpha )## ... ... "When Bland puts ##g(x) = ( x_\alpha )## he seems to be specifying a particular ##g## and then proves ##f = g## ... ... I thought he was proving that for any ##g## such that ##\pi_\alpha g = f_\alpha## we have ##f = g## ... can someone please clarify ... ?Help will be much appreciated ... ...Peter
======================================================================================The above post mentions but does not define ##f## ... Bland's definition of ##f## is as follows:
Peter
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