Here, is induced by the inclusions and by , and is the following map: if is in , then it can be written as the sum of a chain in and one in , . , since . Thus, is a chain in , and so represents a class in . This is . One can easily check (by standard diagram chasing) that this map is well defined on the level of homology.
|Date of creation||2013-03-22 13:14:52|
|Last modified on||2013-03-22 13:14:52|
|Last modified by||bwebste (988)|