2 JHR's MA211 page

# JHR's MA211 page

## MA211 Differential Equations

MTRF 2G221
John Rickert, Associate Professor of Mathematics
Office: G-215A, Crapo Hall
Phone: (812) 877-8473

e-mail: rickert@rose-hulman.edu

Office hours week: MTRF 7, or make an appointment, or drop in. Here's my schedule

Moodle
The Final exam takes place Wednesday, February 20, 2013 1PM-5PM in G310.
To Homework ...Questions
Homework for our next class ...Today's questions
For Tuesday, November 27: Sec. 1.1 #17,21,23; Sec. 1.2 #7,9,11,45. Turn in these exercises on Thursday.
For Thursday, November 29: Turn in the Section 1.1 and 1.2 homework.
Section 1.3 #1-4,9,10,11,19,21,24.
For Friday, November 30: Section 2.1 #1,4,6,13,21,26,30,39. Turn in these exercises on Monday.
Reminder: The DEplot is in the Maple DEtools package. to plot something such as dy/dx = y - x you can use the command
DEplot( diff(y(x),x)=y(x)-x, y(x) , x=-5..5, y=-6..6)

For Monday, December 3: Turn in the Section 2.1 homework exercises.
Section 2.2 #1,6,17,24.
For Tuesday, December 4: Section 2.2 #21,26,33,34,35.
For Thursday, December 6: The average score on the Quiz was 16.5. Equivalent grades are A 18-20 B 16-17 C 14-15 D 12-13.
Section 2.3 #1,3,8,11,14,22,28,48.
For Friday, December 7: Section 17.1 #1,4,6,9,16,28,32,34.

Monday, December 10: Remember that class starts at 8:50 on
December 10.
Section 17.2 #1,2,6,9,12,15,22,28,34. Turn in these exercises on Tuesday.
For Tuesday, December 11: Turn in the Section 17.2 homework.
Section 3.1 #2,4,7,25,27.
For Thursday, December 13: Section 3.3 #1,6,12,30,33.Turn in these exercises on Friday.
For Friday, December 14: Turn in the Section 3.3 exercises from Thursday.
Work the exercises on the homework sheet passed out in class. A copy of the sheet is also on Moodle.

For Monday, December 17: Turn in the exercises from the worksheet (available on Moodle).
Section 3.4 #1,5,10,17,22,28.
Tuesday, December 18: On Exam #1 the average score was 90/125. Equivalent grades are A 105-125 B 90-104 C 70-89 D 55-69 F <55.

For Thursday, December 20: Section 3.4 #13,20,33,37.
For Friday, December 21: Section 3.4 #19,24,29.

For Monday, January 7: Section 3.8 #1,6,11,17.
For Tuesday, January 8: Section 3.8 #2,5,10,13.
For Thursday, January 10: Section 3.8 #29,32,38,39.
For Friday, January 11: Work the homework exercises passed out in class. a PDF of the worksheet is available on Moodle.
For Monday, January 14: Turn in the homeowrk exercises passed out in class Thursday.
Section 3.8 #33,40,43.
The average score on the quiz was 16.5/20. Equivalent grades are A 18-20 B 16-17 C 14-15 D 12-13 F <12.
For Tuesday, January 15: Section 3.8 #15,18,34.
At the beginning of class we will have a quiz about inhomogeneous differential equations.
For Thursday, January 17: Section 4.1 #2,8,11,22.Turn in these exercises on Friday.
At the beginning of class we will have a quiz requiring you to compute a LaPlace transform.
For Friday, January 18: .Turn in Thursday's Section 4.1 exercises: #2,8,11,22.
Work exercises Section 4.1 #14,18,25,29,37,41.

For Monday, January 21: Section 4.2 #1,7,19,24,27. Learn the LaPlace transform rules.
For Tuesday, January 22: Section 4.2 #31,33,36,38.
For Thursday, January 23: Section 4.3 #1,7,8,11,15,24,29,33.
Friday, January 25: For Exam #2 the average was 64.6. Equivalent grades are A 91-103 B 74-90 C 57-73 D 40-56 F <40.

For Tuesday, January 29: Section 4.3 #37,43,46,61,63,68.
For Monday, February 4: Turn in the homework sheet exercises.
Section 4.4 #3,6,13,19,24,32,37.
For Tuesday, February 5: Section 4.4 #49,50,52,57,58.
For Thursday, February 5: Section 4.5 #1,3,6,10,13.

Friday, February 8: the average scoer on Exam #3 was 80/9/120. Equivalent grades are A 100-115 B 83-99 C 66-82 D 49-65 F <49.

For Tuesday, February 12: Section 6.1 #1,6,10,11.
For Thursday, February 13: Turn in the homework sheet exercises.
Section 6.2 #3,8,12.

Answers should be explained. The correct answer will be worth 1 point. The rest of the credit comes from correctly explaining how the answer is found. The words "used Maple" are not an explanation and will result in a loss of 1 point. Similar evasions will also result in a loss of credit.
Homework is due at the beginning of class on the day that it is due. You should turn in your homework in a pile on the desk at the front of the classroom. Homework may be turned in later but will be penalized based on just how late it is - typically
1 point off for turned in late during the class,
5% off for being turned in late the same day,
10% off per day. (weekends count for two days) i.e. 10 days later, it's too late to get a makeup homework turned in.
When writing up homework, you should circle (or otherwise clearly indicate) your answers.
It's good to work together, but you should write/type your own homework. Simply copying another person's work or Maple file is not acceptable.

You should come to class prepared. This means that I expect you to have done the homework, brought your book to class, and silenced your cell phone.
If you have a cell phone, please make sure that it does not ring audibly during class. Phone calls should, in general, not be answered during class. No texting during class.

• If you don't understand something, ASK
• If I'm going too fast, STOP ME. I enjoy mathematics. When I get on a roll, I tend to keep going.
• SHOW YOUR WORK. The correct answer will only be worth 1 point. I want to verify that you understand the process.
• If you are having problems understanding the material, see me or go to the learning center.

### A summary of the grade weights

There will be three in-class exams worth 15% each
The final exam will be worth 30%
Quizzes, homework, and projects will be worth 25%

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