Quiz samples and the quiz itself are created weekly. Links below provide a preview of coming attractions. Lecture details are edited at the beginning of the week and again at the end of the week. Examples are available for weeks 1,2,3 only.

WEEK 1, Jan 9-13  Examples Lecture details
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1.1; differential equation, mathematical model
1.2; integral as a general or particular solution
1.3; slope field
1.4; separable differential equation
First Exercise. Submit Exercise 1.2-2 on Wed Jan 11 for review. Returned with comments on Thu Jan 12 or Fri Jan 13. Details Here.
Quiz1 Sample and Quiz1 Sample Solutions
Take-home Quiz1 and Homework HW1 due Friday next week.
Thursday Problem Session Photo Directory Click Here

Some solved problems from Edwards-Penney can be found from the 2280 course of Professor Nathan Smale (2015) Here.

WEEK 2, Jan 16-20 Examples Lecture details
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Monday Holiday, Martin Luther King. No classes.
1.5; linear differential equation
3.7; LR and RC circuits
Computer Lab 1 details
2.1; mixture model, Malthus and Verhulst models, cascades and compartment models
2.2; autonomous u'=f(u), equilibrium solution, stability, harvesting
2.3; velocity, acceleration, Newton air resistance models
Quiz2 Sample and Solutions with graphs
Take-home Quiz2 and Homework HW2 due Friday next week.
Quiz 2 had a typo: 0.95% instead of 95%
Thursday Problem Session Photo Directory Click Here

WEEK 3, Jan 23-27 Examples  Lecture details
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2.3; Newton model examples, escape velocity, Jules Verne problem.
2.4, 2.5, 2.6; numerical solutions: Rectangular, Trapezoidal and Simpson rules
2.4; Euler method
2.5; Heun or Modified Euler method
2.6; Runge-Kutta method, RK4
Quiz3 Sample and Solutions
Take-home Quiz3 and Homework HW3 due Friday next week. Numerical Project PDF here, due the first class meeting in March
Numerical maple and matlab resources Directory Here
Problem Session on Quiz2 (from 2015) Photo Directory Here
Thursday Problem Session Photo Directory Click Here


WEEK 4, Jan 30 to Feb 3 Lecture details
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Numerical methods, third lecture.
3.1; second order linear equations, Euler solution atoms
3.3; homogeneous constant-coefficient equations, Euler substitution, Euler solution atoms
Tuesday is Lab 1 day, completed in LCB 115.
Quiz4 Sample and Solutions
Quiz4 resource on  Picards's Theorem
Take-home Quiz4 and Homework HW4 due Friday next week.
Thursday Problem Session Photo Directory Click Here

WEEK 5, Feb 6-10 Lecture details
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3.2; general solution, Picard theorem, independence, Wronskian, superposition
3.1-3.3 Continued. Independence. Wronskian Test.
3.4; mechanical vibrations
Computer Lab 2 details
3.5; forced equations, undetermined coefficients, variation of parameters
Maple Lab 1 Intro due this week
Quiz5 Sample with solutions
Take-home Quiz5 and Homework HW5 due Friday next week.
Maple, MuPad, Matlab examples PDF
Thursday Problem Session Photo Directory Click Here
One week warning: Midterm Exam 1 on 17 February over weeks 1 to 5
Study Sample Exam 1 with solutions (posted 9 Feb 2017)
Study for matching content Old 2250 Exams which used Edwards-Penney. Ch 1,2,3 in 2280 == Ch 1,2,5 in 2250.

WEEK 6, Feb 13-17 Lecture details
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3.6; mechanical resonance
3.7; LRC model, electrical resonance
Maple Lab 2 Newton Cooling (pipes or cooler project) due this week.
  The swamp cooler PDF was corrected 18 Apr.
Quiz6 Sample with solutions and the network problem Solution
Take-home Quiz6 and Homework HW6 due Friday 24 Feb (after Exam 1).
Friday, 17 Feb, Midterm Exam 1 at 12:50pm until 1:50pm, over weeks 1 to 5
Midterm Exam 1 2017 How To Use It
Thursday Exam Review Blackboard Photo Directory 

WEEK 7, Feb 20-24 Lecture details
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Monday Holiday, President's Day. No classes.
7.1; Laplace, properties, table, piecewise continuous, existence, Lerch's theorem, inverse Laplace
7.2; derivative theorem L(y')=sL(y)-y(0) and extensions, spring-mass system, modeling, integral theorem
7.3; partial fractions, Heaviside's method, shift theorem, resonance


Thursday Problem Session 12:55pm blackboard photo directory
Maple, MuPad, Matlab examples Click Here
Quiz7 is extra credit this week, due to Exam 1:
 Sample quiz7
Take-home Quiz7 and Homework HW7 due Friday of week 8.


WEEK 8, Feb 27 to Mar 3 Lecture details
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4.1; first order system, brine cascade, spring-mass system, electrical network, Picard theorem [integrated with Ch 7]
7.4; convolution, s-derivative theorem, t-integral theorem
7.5; unit step, pulse, ramp, second shift theorem, spring-mass, circuits, periodic function theorem
Quiz8 Sample with interleaved solutions.
Take-home Quiz8 and Homework HW8 due Friday Week 9.
Thursday problem session 12:55pm blackboard photo directory

WEEK 9, Mar 6-10 Lecture details
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7.6; Dirac impulse, hammer hit model, unit impulse response, unit step response
5.1; matrix systems u'=F(u), u'=Au+g(t), superposition, vector-matrix Picard theorem
4.2; Cayley-Hamilton-Ziebur method (Example 4.2-1), Elimination method, Cayley-Hamilton theorem.
Computer Lab 3 and Lab 4 details
   maple Lab 3 laplace due Friday Week 11 (week after Spring Break)
   maple Lab 3 laplace, maple text for mouse-paste.
   maple Lab 4 resonance due Friday Week 13
   Maple from home, UofU Library Remote Maple 18 How To Use It
Extra Credit Quiz9 Sample with interleaved solutions.
Extra Credit Take-home Quiz9 is offered.
Homework HW9 due Friday after Spring Break, week 12.
Thursday Problem Session 12:55pm blackboard photo directory
Due Friday week 11: Quiz8  (Linear DE, Laplace table),  Quiz11 (Laplace), HW8 (Ch 7 Ch4 problems).

WEEK 10, Mar 11-19 is Spring Break. No classes.
=======
No Lab. No Quiz10. No HW10.
Maple, MuPad, Matlab examples PDF

WEEK 11, Mar 20-24 Lecture details
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Maple Labs 3 and 4, Tuesday session in LCB115 for 30 min: 
   maple Lab 3 laplace due this Friday Week 11 (week after Spring Break)
   maple Lab 3 laplace, maple text for mouse-paste.
   maple Lab 4 resonance due Friday Week 13
4.3; RK4 numerical algorithm for systems.
  Example 1: PDF: maple for section 4.3
  SYSTEM Reference: Manuscript: Numerical methods for systems
  Slides: Numerical methods, scalar and vector formulas
5.2; Eigenanalysis method for u'=Au, brine tank cascades
5.3; mechanical systems Mx''=Kx, eigenpair solution, railway cars, resonance, earthquakes
   Slides: Cayley-Hamilton-Ziebur Method for u''=Au
5.4; generalized eigenpair, Jordan's two theorems, Cayley-Hamilton
5.4; Jordan form, chain algorithm, railway cars
Chapter 5 maple examples source directory
Computer Lab 3 Laplace due this week.

Quiz11 Sample with interleaved solutions.
Take-home  Quiz11 and Homework HW11 due Friday next week.
                                                                                                                      
Thursday Problem Session 12:55pm blackboard photo directory, problems 1, 7 on Sample Midterm Exam 2.

One week warning: Midterm Exam 2 on Friday 31 Mar
Study for Midterm 2 on Mar 31: Sample Exam 2 Problems only, Sample Exam 2 Problems and solutions
Old Exam 2 Problems and solutions from 2016

Study for matching content Old 2250 Exams which used Edwards-Penney.
Exam 2 will cover topics from week 6 to Friday of week 11. Only topics on the sample exam will appear on Exam 2.

WEEK 12, Mar 27-31 Lecture details
=======
5.5; matrix exponential, Putzer algorithm, fundamental solution

Quiz12 Sample and Sample Solutions
Take-home Quiz12 and Homework HW12 due Monday 10 April
The answer to problem 2(c) has been corrected. Browser refresh will show the replacement.
    Maple references for Exercises 6.3-4,5,6,7: PDF and WORKSHEET
    Maple reference for Exercises 6.3-8,9,10: WORKSHEET
Exercises Edwards-Penney Chapter 5 Fourth Edition

Thursday Exam Review 12:55pm blackboard photo directory, Exam 2 review
Study for Midterm 2: Sample Exam 2 Problems only, Sample Exam 2 Problems and solutions
Old Exam 2 Problems and solutions from 2016


Friday 31 Mar: Midterm Exam 2 at 12:50pm until 1:50pm, over weeks 6 to 11
      2017 Midterm 2: Exam 2 Problems only, Answers later.

WEEK 13, Apr 3-7 Lecture details
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5.6; vector-matrix variation of parameters, 3-tank brine cascade
6.1; equilibria, stability.
6.2; phase portraits for non-linear systems, Paste Theorem
To be skipped due to lack of time:
Computer Lab 5 details
skipped: 6.3; populations and ecological models, predator-prey, competition, survival, extinction
   Maple references for Exercises 6.3-4,5,6,7: PDF and WORKSHEET
   Maple reference for Exercises 6.3-8,9,10: WORKSHEET
skipped: 6.4; nonlinear mechanical systems, hard and soft springs, nonlinear pendulum,
skipped: 6.5; chaos, period doubling, pitchfork bifurcation, York-Li, Feigenbaum. Examples: Duffing, Lorenz, Roessler
Thursday Problem Session 12:55pm blackboard photo directory

One week warning: Midterm Exam 3 on Friday 14 April
Study S2017 Sample Exam 3 questions and answers.
Reference Old Exam 3 Statements and handwritten solutions (Spring 2016)

No take-home quiz this week or next.
Skipped: Homework HW13 never due
Extra Credit Maple Lab 4 Resonance due May 4.
Extra Credit Maple Lab 5 due May 4: PDF: maple Lab 5 brine tank
Extra Credit Labs due Thursday May 4. See Extra Credit PDF Sources

WEEK 14, Apr 10-14 Lecture details
=======
9.1; periodic time signals, Fourier series, Gibbs overshoot, signal reconstruction from sampling, mpg music
9.2; Fourier-Dirichlet convergence theorem, Fourier coefficients, signal approximation, graphical intuition
9.3; Even and odd signals, Fourier sine and cosine series, differentiation and integration of Fourier series

No Take-home Quiz this week.
Homework HW14 due May 4.

Thursday Exam Review 12:55pm blackboard photo directory
Study S2017 Sample Exam 3 questions and S2017 Sample Exam 3 solutions
Reference Old Exam 3 Statements and handwritten solutions (Spring 2016)

Friday, 14 April, Midterm Exam 3 at 12:50pm until 1:50pm, over weeks 11 to 13. 
Study the sample exam and reference exam posted above.

WEEK 15, Apr 17-21  Lecture details
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9.4; Steady-state periodic solution, observable, damping effects, mechanical and electrical forcing effects
9.5; heat conduction, boundary value problem, superposition, separation of variables solution
9.5; ice-pack ends. Dirichlet problem.
9.6; Finite string equation in one dimension. Steady-state heat conduction on a plate.

Homework HW15 due by 6pm Thursday May 4 under the door JWB 113.
Study the Sample Final Exam Questions and Answers and Short Sample Questions only
Study the Final Exam Study Guide

Chapter 9 PDE slides: directory
Chapter 9 PDE problems, 4th edition: directory

Thursday Problem Session and Exam Review 12:55pm blackboard photo directory


WEEK 16, Apr 24-25 Lecture details
=======
Sample Final Exam. Covers Chapters 1 to 9, skip Chapter 8.
Comprehensive Final Exam review started on Tuesday.
Study the Sample Final Exam Questions and Answers and Short Sample Questions only
Study the 2016 Final Exam (last year) Questions only and Questions with solutions
Study the Final Exam Study Guide

Final Exam Review sessions blackboard photo directory (26 Apr 4:30-6:30pm)

WEEK 17
=======
Final Exam Review Tuesday 26 Apr in LCB 219 4:30pm to 6:00pm

Final Exam Review sessions blackboard photo directory
Shortened sample final exam Questions

Finals week: Comprehensive final exam, Friday April 28,  12:45pm to 3:15pm in LCB 219
Extra credit homework and labs due by 6pm, under the door 113 JWB, Thursday May 4.
Homework HW15 due by 6pm, under the door 113 JWB, Thursday May 4

2017 Final Exam Questions with student solutions

Sample Maple Code for 2280

The directory also contains copy-and-paste text maple sources, identified by file extension TXT or MPL.
Click Here for directory access

Maple, MuPad, Matlab command examples PDF
Starting Maple, MuPad, Matlab from a remote terminal login. Text interface, no graphics.TEXT Here

Maple Tutorials

1. Maplesoft Quick Reference Cards Click Here
2. Douglas Meade's Quick Reference Card for Maple 12 to Maple 2015 Click Here
3. A rookie maple tutorial (also Matlab and Mathematica) for the impatient from Indiana University Click Here
4. Maple programming examples by topic from Kettering University Click Here
5. Utah Maple tutorial 2017 in html format. Includes Setup and First Use.
   Used in LCB115 maple intro lectures.
   Click Here
6. How to use maple 2015 under unix, windows, OS/X (text)
   Here
7. Maple graphics and low speed internet
   Maple at home
8. Peter Stone's Maple Resource page for undergraduate math topics Click Here

Matlab Tutorials

1. A one-page pdf Matlab cheat sheet from Strang's linear algebra course at MIT Click Here
2. A matlab tutorial at MIT, contains basic information. No video camera, only code examples and text information. Link is HERE
3. Mathworks matlab tutorials and documents are HERE. Register for the short tutorials, then try a few using your univ of Utah computer account. Matlab has a site license valid for all campus computers.

Remote Maple: Running Maple from Home

Maple can be run from home, a laptop, or even a phone or tablet, using a minimal internet connection. Instructions here for the UofU Library and the Math Department computers:
Maple from home, UofU Library Remote Maple 18 How To Use It

Mathematica Tutorials

1. Printed or free PDF tutorials on special topics are available at Wolfram Research: HERE
2. New users can start with John McLoone's YouTube video (2010) HERE
3. A complete set of short tutorial videos are available at Wolfram Research, addressing special topics HERE
4. Wolfram videos and screencasts cover a wide range of applications and interests. See Wolfram Broadcast Videos

Homework Problems

The Calendar has the problem list(s), one PDF source per week. The Calendar is the most reliable source for finding due dates and the problem list.

The homework PDf files linked in the Calendar are labeled HW1, HW2, ... and they can be found in this Directory, which may be a quick way for you to check what is due.

The Bookmark is a complete list of what is due on Friday each week, 2 pages in length, suited for folding into your textbook. Find the PDF here: Bookmark

There is little difference between 4/E and 5/E editions of the textbook Differential Equations and Boundary Value Problems: Computing and Modeling. The major difference is isolated to Chapter 5. In chapter 5, the 4/E problems agree exactly with the 5/E problems, except for numbering of sections, and an inserted section 5.3 (5/E). This causes the section numbers to be off by one, but the problem numbers are exactly the same. The HW problems will use the 4/E problem numbers, to stop confusion, with web site warnings about mis-matched problem references. The chapter 5 contents appear below, where 4/E==4th Edition and 5/E==5th Edition.

Chapter 5.  Linear Systems of Differential Equations
5.1 in 4/E and 5/E:  Matrices and Linear Systems
5.2  in 4/E and 5/E: The Eigenvalue Method for Homogeneous Systems

5.3 in 5/E only: A Gallery of Solution Curves of Linear Systems       [Inserted 2015]

5.3 in 4/E == 5.4 in 5/E:   Second-Order Systems and Mechanical Applications
5.4 in 4/E == 5.5 in 5/E:   Multiple Eigenvalue Solutions
5.5 in 4/E == 5.6 in 5/E:   Matrix Exponentials and Linear Systems
5.6 in 4/E == 5.7 in 5/E:   Nonhomogeneous Linear Systems

Therefore, you can use 4/E instead of 5/E. If you own edition 4/E, and you want to obtain a copy of the missing material 5.3 (5/E), then Copyright issues arise. Please know that the course web site has free PDF slides and PDF manuscripts on the topics covered in section 5.3 of 5/E. These resources have been in use for 5 or more years, and they will replace section 5.3 in the lectures. No homework is assigned from A Gallery of Solution Curves of Linear Systems.

Maple Computer Labs

There are seven (7) labs offered. The last four are extra credit, intended to replace math problems or computer labs.

1. First Maple Lab never due, done in first LCB115 meeting
2. maple Lab 1 intro due Week 5
3. maple Lab 2 freezing pipes due Week 6 (choose pipes or cooler)
4. maple Lab 2 swamp cooler due Week 6
   Lab 2 swamp cooler corrected 18 Apr.
5. maple Lab 3 laplace due Week 11 (week after Spring Break)
6. maple Lab 4 resonance due Week 13
7. maple Lab 5 brine tank due May 4
8. maple Lab 6 narrows due May 4
9. maple Lab 7 earthquake due May 4

Thursday Problem Sessions

Weekly Thursday sessions are held in LCB 219 at 12:50pm, to discuss HW due the next week. For example, Thursday of Week 4 would discuss HW4, which is due in Week 5. Blackboard photos of the Thursday session are posted, a link appearing in the Calendar.

Bookmark of Problems Due

A bookmark can be printed, to fold into your textbook. The bookmark contains all the textbook problems and computer problems. Enumeration is by week, where Week 10 is Spring Break, no homework in Week 10. Use this print to journal your homework assignments. Bookmark Here

Problem Notes for Graded Problems

Problem Notes exist, organized by chapter, for Chapters 1-7 and 9. Click here for the problem notes
These notes sometimes have answers which are either not in the book or are different from the book answers. The notes originated from email messages, office visits and grader remarks.

Extra Credit Problems and Extra Credit Maple Labs can be found Here
These problems replace scores of zero or 50 on homework. They do not affect exam scores or quiz scores.
Extra credit is also possible by submitting an extra credit maple lab. Submit by May 4. Maple labs 5, 6, 7 are extra credit.

Studying for Exams. Please read the study guide problems, none of which are due. For example, HW3 lists 2.4: 2, 3, 4, 10, 12, 17 as study problems and boxed problem 6 as due in week 4. Reading the problems is important for developing problem-solving intuition. Mostly, you look for problems that you know how to solve. Any mystery detected should be solved: be a good detective.

Sample Exams will be posted in the calendar when available.
Exam 1 S2017 solutions are posted one week after the exam date.
Sample Exam 1 S2017: Sample Exam 1 with solutions for Midterm 1 on Friday, Feb 17.
Similar 2280 exams were last given Spring 2016. The S2016 web site can be found Here.

Exam Solution Keys are posted in the calendar, as they become available.
Find old 2280 exam keys from Spring 2016 in the calendar at the web site link above.

Math 2280-2 Differential Equations

US Mail address:

        Grant B. Gustafson
        155 South 1400 East Room 233
        Salt Lake City, UT 84112-0090

Office phone: (801) 581-6879, in room JWB 113
Email Address: Read the online DoorCard
Course Syllabus: The 2280-2 course syllabus for 2017 can be found Here (288K pdf)
2280 Format Ideas for Written Reports
How to improve your written work, Writing reports. ( 79K pdf)

Internet archived files from previous semesters exist, which have homework solutions, maple and matlab code, exam keys, syllabi and problem notes.
A sampling of what is available can be found at Professor Korevaar's site, which is mainly for instructors, but applicable to you, if you are searching for 2280 information.
Korevaar's list of previous 2280 instructors and home pages
To find more Utah 2280 courses, start with the math department course schedule page. Then find instructor names and section numbers for 2280, for the past 3-4 years. Go to the math department Main Page to find the home pages of those instructors. Track down the old 2280 course from their home page. If this idea fails to give information, then try an internet browser search for "korevaar 2280" and "smale 2280" and see what surfaces.