HW 9 answer error

There was an error in my solution to problem 9 (b) on Homework Set 9: I originally said that all three poles were inside  the given circle.  Actually, only the two poles 0 and 1 + i are inside.  Hence from the Residue Theorem the correct value of the contour integral should be π/2 + (π/2) i.

I’ve uploaded a corrected version of the solutions to the Math 421 UDrive.

In case you lost credit on #9 (b) because of my error, please bring your paper with you to the exam Tuesday and I’ll fix it.

(If I marked that problem as correct because of my mistake, you need not show me your paper to get any credit deducted!)

Exams Homework

End-of-semester information

Office hours

Monday 13 December 2:00–4:00 p.m., my LGRT 1335G office.

You may pick up your graded Homework 9, or any previously uncollected exam or homework paper.

Homework 9 solutions

Complete solutions have been uploaded to the usual UDrive location.

There were some too-common errors made in Homework 9 solutions, especially some conceptual errors. Please see this list of common errors there.

Final Exam

  • Reminder that the Final Exam Tuesday (at 8:00 a.m.) is in our usual classroom, LGRT 219
  • I’ve posted a list of the additional Final Exam topics—the ones since Exam 2. Lists of topics from Exams 1 and 2 are there, too.

Final exam: Tues 14 Dec 8:00-10:00 a.m. LGRT 219

The Math 421 Final Exam is:

Tuesday, 14 December
8:00–10:00 a.m.
LGRT 219 (our usual classroom)

In case of a final exam conflict, you must provide me with written documentation from the Registrar’s Office no later than Tuesday, 1 December.

You have a final exam conflict only if there is another officially-scheduled final exam at the same time.

To see which in which course you are entitled to a final exam make-up, look at the last digit of the 5-digit class number of the other course and of Math 421. Our class number is 73992. You are entitled to a make-up for the exam in the course where that digit is higher. Thus if the other course has the last digit of the 5-digit class number 3 or higher, then you get a make-up for the final there. If the last digit of the other course’s class number is 2, the same as ours, then look at the next-to-last digit, etc.

Such documentation, signed by a representative of the Registrar, should include:

  • The course whose final exam conflicts and the 5-digit class number for that course
  • Contact information for the instructor of that conflicting course
  • A copy of your entire final exam schedule
  • Your contact information: UMass e-mail address and telephone number

Exam 2 solutions available

For complete solutions to Exam 2 (and indication of how credit was divided within questions), see the link “Get Exam 2 solutions” on the Exams page.


Exam 2 statistics

Here are statistics on Exam 2 scores. (The data excludes the score for one student who did none of the homework sets.)