Math 448: Modern Algebra I

Assignment #8 – Due Thursday, Oct 1, 2026
  1. Prove the theorems and answer the questions in this Lurch document. Save it in your Dropbox folder in a subfolder named assignment 08 (lower case, one space, a zero before the 8, no # or hyphens). No AI or Google! Yuk! 🤮
  2. Putnam Training! (optional bonus points) Continue to optionally work on the bonus problems in Round 1 of this year’s USAMTS competition. Game on!

Course Handouts and References

  • Lecture Notes – check here often for revised lecture notes for our course
  • Course Syllabus
  • Proofs – notes and Lurch contexts from my Math 299 course on mathematical proofs

Software and Handouts

  • Lurch – a math word processor that can check your proofs!
  • Overleaf – a free website where you can easily produce LaTeX math documents through a web browser
  • Toy Proofs – a “toy” proof system I developed to introduce students to the concept of formal proofs.
  • Group Explorer – amazing group visualization and exploration software from Nathan Carter

Homework Assignment Template

Putnam!
Tentative Schedule
#DateTopic
1 Tue, Sep 1 Introduction; Logic and Proof
2 Thu, Sep 3 Appendix B,C,D (equivalence relations & induction)
3 Tue, Sep 4 Section 1.1: Division Algorithm
4 Thu, Sep 10 Section 1.2: Divisibility
5 Tue, Sep 15 Section 1.3: Primes and Unique Factorization
6 Thu, Sep 17 Section 2.1-2.2: Congruence and Modular Arithmetic
7 Tue, Sep 22 Section 2.3: $\mathbb{Z}_p$ when $p$ is prime
8 Thu, Sep 24 Section 3.1: Rings
9-10 Tue, Sep 29 Section 3.2: Basic Properties of Rings
11 Thu, Oct 1 Section 3.3: Isomorphism and Homomorphism
12 Tue, Oct 6 Section 4.1: Polynomials and Division Algorithm
13 Thu, Oct 8 Section 4.2: Divisibility in $F[x]$
14 Thu, Oct 15 Section 4.3: Irreducibles and Unique Factorization
15 Tue, Oct 20 Section 4.4: Polynomial Functions, Roots, and Divisibility
16 Thu, Oct 22 Section 5.1: Congruence in $F[x]$
17 Tue, Oct 27 Section 5.2: Modular Arithmetic in $F[x]$
18 Thu, Oct 29 Section 5.3: $F[x]\left/p(x)\right.$ when $p(x)$ is Irreducible
19 Tue, Nov 3 Section 6.1: Ideals and Congruence
20 Thu, Nov 5 Section 6.2: Quotient Rings and Homomorphisms
21 Tue, Nov 10 Section 7.1: Groups
22 Thu, Nov 12 Section 7.2: Basic Properties of Groups
23 Tue, Nov 17 Section 7.3: Subgroups
24 Thu, Nov 19 Section 7.4: Isomorphisms and Homomorphisms
25 Tue, Nov 24 Section 8.1: Congruence and Lagrange’s Theorem
26 Tue, Dec 1 Section 7.5: Symmetric and Alternating Groups
27 Thu, Dec 3
28 Tue, Dec 8
29 Thu, Dec 10