21-241: Online Assignment #13

There was an error in the way Problem #5 was being graded on this week's assignment. I'm pretty sure I figured out the problem and fixed it. If it was giving you problems, give it another try.

21-241: Week #5 Online Assignment

One of the problems I'd included on this week's WeBWorK assignment (Problem 7) was not being scored correctly. I was not able to fix the problem, so I removed it from the assignment. When you look at it now, you will see there is no Problem 7. It jumps form Problem 6 to Problem 8. Do not be alarmed!

21-241: Lecture 7

On Wednesday, September 10, we discussed the "Geometry of Linear Systems of Equations." I devoted a significant amount of time to discussing the "Row Picture" and the "Column Picture." This terminology does not appear in our textbook. I found these ideas in a previous semester when we used Linear Algebra and It's Applications by Gilbert Strang as the textbook. This book is being used by another instructor this semester, so copies are floating around. The topics I discussed are in Section 1.2 of that book.

21-241: Lecture Notes

I've fallen a little behind in the lecture notes, but notes through Friday, September 5, are available on the Blackboard site.

21-241: Lectures 4 and 5 - Logic

As you have seen, I referred you to this Introduction to Mathematical Arguments for our two lectures on logic and proof. I wanted to point you toward this additional resource for another view of the subject.

21-241: Class Notes

I've posted the notes from Lecture 1 on the Blackboard site. They are in the "Course Content" area. I'll try to get notes written for each lecture, but I can make no promises!

21-241: Week #1

The assignemnts for Week #1 have been posted on the Schedule page. Note that you will have to click through some links to get to the homework problems that are due on Friday.

The textbook introduces the idea of a matrix slightly earlier than we will in class - only a day or two, but it makes a difference due to the timing of HW#1. The homework problems selected will not require you to think in terms of matrices. We'll save that for next week.

21-241: Lecture 1

Today's lecture covered Section 2.1 in the text. As I mentioned in class, we will be covering topics in a different order that the textbook, and so at times topics will be mentioned in the text that we will not yet have discussed. You will note that in Example 2.6, the textbook introduces the idea of a matrix, which we will not use in class until Friday.

21-241: Fall 2014

Welcome to 21-241 Matrices and Linear Transformations for the Fall 2014 semester. I'll post information and updates about the course on this blog. The main source of information about the course is the Course Home Page, and in particular, the Schedule Page. There is a Balckboard site for the course, which will be used to record your grades, and distribute solutions.

21-260: Edits to Online Assignment #2

I need to make some comments and clarifications about this week's online assignment.

1. First, you need to find a differential equation, but you do not need to solve it! Also, I give you information that leads to an initial condition. You should enter an initial value problem (i.e. a differential equation with an initial condition) as your answer. I've updated the question to reflect this.
2. When I wrote this problem, I made a mistake that has caused the interest rates to be very small. That's okay, though. We can live with that. Also, I accidentally wrote "mayment" instead of "payment." Finally, the numerical value of k that you enter should be in units of [$ per year]. Your answer should be to the nearest dollar. Blackboard won't let me make these corrections/updates in the problem, though.
3. This is a linear differential equation, which we will discuss in class tomorrow. If you work out the answer to 2 decimal places, you should be okay.
4. Same as for problem 3.