# Tag Archives: announcement

## IMPORTANT – Bring Written Work Chp 4-5 to class on Thursday

Hi everyone,

If you picked up your (graded) written work from Chapters 4 and 5 today, please bring it with you on Thursday to class — I need to record your score in my gradesheet, or you will not get credit for the assignment.  Oops!

Thanks,

Prof. Reitz

## Exam Review 2 UPDATE – review of division and remainders

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 $b>0$, there exist unique integers q and r for which $a=qb+r$ and $0\leq r .

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 $r=0$ means $a=qb$), and if the remainder is not zero, then b does not divide a.

If you have any questions, feel free to leave a comment here.  Best of luck with your studying!

-Prof. Reitz

## Followup on Today’s Lecture (Tues 10/8)

Hi everyone,

In the homework from today, the final two problems (#15, 16) use an idea called “Proof by cases” (considering different possible situations within your proof).    To complete these two problems, read Page 96 (starting with “4.4 Cases” and ending at the end of the first proof, at the bottom of the page).  Bring your questions on Thursday!

-Prof. Reitz

## Office hours today (10/4): 12pm-1pm

Hi everyone,

Office hours today will be from 12pm-1pm (I will also be able to answer a quick question or two right after class).

-Prof. Reitz

## Problems with our OpenLab site

Hi everyone,

A number of you have pointed out that our site is having problems – I’ve submitted a bug report, and will keep you posted.  Don’t worry – if it’s not resolved soon I’ll extend the deadline for OpenLab assignment #2.

Sorry for the trouble!

Prof. Reitz

## The review sheet is too darn long

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

## Office hours today are all messed up

Hi everyone,

Due to several meetings (the curse of a big institution), my regularly scheduled office hours will be all messed up today.  I’ll be available:
– Directly after class for about 12 minutes (until 11:27)
– From 12:30-1:00

If need more time with me, please let me know either at the end of class or by email, and I’ll do my best to find a time that works

.Apologies for the late notice,
Prof. Reitz