As discussed, there is no class Tuesday, Jan 27. You should read
sections 22 and 23 carefully. There are a few important ideas in those
sections (such as multi-variable polynomial rings and
Eisenstein's criterion),
that have not been discussed in class.
Class will meet Jan 29. Sebastian Pauli will be there to discuss the
problems in sections 22,23.
Quiz II (Take-home: Due 02/05.)
Note - the quiz says due 02/04 - that's a misprint.
In class, we discuss using integral matrices and the Smith normal
form to compute quotients of free abelian groups. This material is not in
the text, but can be found in many versions on the internet and in
algebra texts.
Here are some brief notes.
For more information, you might start with
the Wikipedia version. More detail and proofs about elementary matrices can be found in some
online notes by
Ralph Howard.