UPDATE 12/17: Corrected the answer to problem 14a (see comments below).
The Answer Key appears at the end of the review sheet, which is posted on the “Exam Reviews” page. Let me know if you find any errors, or have any questions.
Best of luck,
Prof. Reitz
You can find a link to it on the “Exam Reviews” page, here. Answer key will be posted by the end of the week. If you have questions, don’t hesitate to send me an email or leave a comment here.
Good luck!
– Prof. Reitz
UDPATE 2 (11/5): The proof of #10 had a typo.
Near the end, after the line “Subtracting 504 from both sides”, the right side should end with a “-504” rather than “+504”. Similarly, in the next line, the final parentheses should end with “-56” rather than “+56”.
UPDATE: The answer key has been added to the review sheet – let me know if you find an error!
Hi everyone,
Be aware, there was typo in problem number #9. The left side of the equation should end in “n(n+2)” instead of “n(n+1)”. Apologies for this error!
-Prof. Reitz
Hi everyone,
Your third exam will take place next Thursday, November 21st. The review sheet is posted on the Exam Reviews page (solutions will be added over the next few days). Feel free to post questions or comments here!
Best of luck with your studying,
Prof. Reitz
Hi everyone,
Two things about the review sheet:
1. There is a typo in problem #5c — it should read |X|=3, instead of |A|=3.
2. As I told a number of you in my office today, I will NOT put a problem like #12 (There is no largest prime number) on the exam.
Best of luck with your studying,
Mr. Reitz
Hi everyone,
If you have questions for me BEFORE the exam on Thursday, I can be available tomorrow (Tuesday) between 1 and 2 pm, BUT only if you notify me ahead of time (by email, or by leaving a comment here, or by telling me in class tomorrow).
Best of luck with your studying,
Prof. Reitz
Hi everyone,
First, the answer key for the Exam 2 review is now complete (it follows the questions in the Review document). Second, you will notice that there are a few places (especially in problems 8 and 12) that I use basic facts about remainders when one number is divided by another. These are facts that you understand intuitively from working with dividing numbers, but it might help to have them stated explicitly. This is the basic fact about dividing and remainders:
Fact (The Division Algorithm). Given two integers a and b with 
What does this mean? It expresses the fact that when we divide one integer a by another integer b, and it will go in some number of times q with a remainder of r. The remainder r must be less than the number b that we are dividing by. If the remainder is zero, then b divides a (because 
If you have any questions, feel free to leave a comment here. Best of luck with your studying!
-Prof. Reitz
Posted in Uncategorized
Tagged announcement, division, division algorithm, exam review, remainder, update
Find it on the “Exam Reviews” page (link in the menu above the shark). Answers to the review will be added to the document sometime this week. If you have any questions or notice any errors please let me know.
-Prof. Reitz
This review sheet is rather long – because of this, I’ve marked certain problems as optional (denoted with a double asterisk **). If you have only a limited time for review, do the other problems first. If you have a little extra time, the ** problems are good practice.
Optional Problems: 1b, 2d, 4bf, 5efij, 6ae, 7c, 8d, 10a, 12b
Homework Week 4
Written work – none
WeBWorK – Assignment3-Sec2.1-2.6 (Due Tuesday, 9/24, at midnight)
OpenLab – none
Heads up: Exam #1 is next week Thursday, 9/26. Review sheet is posted on the OpenLab, answer key will be added within the week.
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