MATH 423 Fall 2018

Basic Information

  • Instructor: Jeff Thunder
  • Office: WH 320
  • Phone: 753-6725
  • e-mail:
  • Office Hours: MWF 1:30-2:30 or by appointment

Course Outline and Objectives

We will be using the text Linear Algebra (Fourth Edition) by Friedberg, Insel and Spence. We will be covering all of the material in the text, with just a few exceptions. The student is expected to acquire an understanding of linear algebra somewhat deeper than the level of the standard sophomore level course (such as NIU's MATH 240). Students are expected not only to follow the proofs presented in class and in the text, but also to construct proofs of their own. Proofs must be logically correct and care must be taken to write precisely and in grammatically correct English.

Grading Scale

Grades will be based on homework, a midterm, and the final exam. The weights for these are 55%, 15%, and 30%, respectively.


Homework will be collected once a week on Mondays. It will be turned in at the beginning of class. You are free to work with other students on the homework; in fact, this is encouraged. Sloppy and/or illegible work will be returned back with no credit! Your homework is something of which you should be proud (notice how I didn't end with a preposition there). Expect to spend lots of time on it. All of the homework problems will be checked to see that each has been done, and certain of the problems will be graded in detail, but just which problems from each assignment will be graded will not be announced in advance. The specific assignment for each week will be available on this webpage.


The final exam is scheduled for Wednesday, December 12 from 10:00 to 11:50 a.m.; the midterm exam will be on Friday, October 19 during our regular class time.

Homework Assignments

  • Week #1 (Due Wednesday, September 5)
  • Week #2 (Due Monday, September 17): Exercises 12, 32, and 33 from section 1.6 and 3, 13, and 14 from section 2.1
  • Week #4: Exercises 2, 11, and 15 from section 2.2 and 12, 16, and 17 from section 2.3.
  • Week #5: Exercises 13 and 17 from section 2.4 and exercises 6, 9, and 10 from section 2.5.
  • Week #7: Exercise 8 from section 3.1, exercises 8 and 19 from section 3.2, exercise 2 (but over the integers modulo 11) and 10 from section 3.3, and exercises 8 and 10 from section 3.4.
  • Weeks #9 and #10: Write definitions for the objects indicated in class, give relevant examples/counter-examples, and state some major theorems regarding these objects.
  • Week #11: Exercises 3, 4, and 8 from section 5.1.
  • Week #13: Exercises 5 and 17 from section 5.4, and exercise 2 from section 7.1.


DRC Statement

If you need an accommodation for this class, please contact the Disability Resource Center as soon as possible. The DRC coordinates accommodations for students with disabilities. It is located on the 4th floor of the Health Services Building, and can be reached at 815-753-1303 or

Also, please contact me privately as soon as possible so we can discuss your accommodations. Please note that you will not be required to disclose your disability, only your accommodations. The sooner you let me know your needs, the sooner I can assist you in achieving your learning goals in this course.

Academic Conduct

Academic honesty and mutual respect (student with student and instructor with student) are expected in this course. Mutual respect means being on time for class and not leaving early, being prepared to give full attention to class work, not reading newspapers or other material in class, not using cell phones or pagers during class time, and not looking at another student's work during exams. Academic misconduct, as defined by the Student Judicial Code, will not be treated lightly.

Homer does math!

Yes indeed, there's plenty of math humor to be found in the Simpsons. Just look and see!

Last update: November 30, 2018