Math 285

Spring 2026 University of Nevada Reno

285 DIFFERENTIAL EQUATIONS (3+0) 3 credits

Theory and solving techniques for constant and variable coefficient linear equations and a variety of non-linear equations. Emphasis on those differential equations arising from real-world phenomena. Prerequisite: MATH 283 (or 182 with permission of instructor).

Instructor  Course Section                     Time              Room
------------------------------------------------------------------------
Eric Olson  Math 285 Differential Equations    MWF 11-11:50am    PE104

Course Information

Instructor:
Eric Olson
email:
Please contact me through WebCampus
Office:
MWF 12:30-1:30pm in DMS 238 and through Zoom by appointment
Homepage:
http://fractal.math.unr.edu/~ejolson/285/

Course Textbook:
Dennis G. Zill, Differential Equations with Modeling Applications, 10th Edition, 2013, Brooks Cole Thomson Learning.

Supplemental References:
Boyce and Diprima, Elementary Differential Equations and Boundary Value Problems, Seventh Edition, 2001, John Wiley & Sons, Inc.

An Introduction to Ordinary Differential Equations by James C. Robinson, Cambridge University Press, 2004.

Student Learning Outcomes

We will cover selected sections in Chapters 1 through 5, 7 and 8 of the textbook. Upon completing this course, a student shall be able to

Information about Software

I will occasionally use the Julia programming language in class to draw graphs and perform simple calculations. This software is free to download for Windows, MacOS and Linux.

Class Handouts

Course materials specific for this section of Math 285 are available by clicking on this link. Details for how to access these files may be found on our course page in WebCampus.

Lecture Notes

Homework

Homework is available on Webassign to help you learn the material. There are also exercises at the end of the each chapter in the text. Solutions to homework problems will not be part of your grade. The goal of homework is to help you to understand key concepts and to master the skills you will need to succeed in this course.

To access the online homework go to www.webassign.net and use the code

unr 5078 7833

You will be asked to set up a Webassign account if you do not already have one. Please use exactly the same name and email you use to register for courses at UNR.

Following is a list of homework problems from the 10th edition of the textbook that should help prepare you for the quizzes. Similar problems appear in the online homework and can also be created by typing a representative question into generative AI and asking the model to create a similar problem for you to practice.

Quiz 1 will focus on Homework 1 and similar problems, Quiz 2 will focus on Homework 2 and so forth. All exams are comprehensive and include material from earlier quizzes and exams plus the indicated additional sections.

Homework 1 (Quiz 1)
Section 1.1#3,5,8,9,11,13,15,27,29,31,55
Section 1.2#1,3,5,9,13,17,23,31,32,33,34
Homework 2 (Quiz 2)
Section 2.1#1,2,21,26
Section 2.2#1,7,15,17,23,25
Homework 3 (Quiz 3)
Section 2.3#1,3,5,7,23,25
Section 2.4#1,5,8,12,15,16,28
Homework 4 (Quiz 4)
Section 2.3#27,31
Section 2.4#31,33,34
Section 2.5#1,5,7,9,15,17,21,27,29
Homework 5 (Quiz 5)
Section 2.6#1,3,5,7
Section 9.1#1,4,9
Section 9.2#5,9,11
Homework (included on Exam 1)
Section 4.1#1,15,21,23,27,29
Section 4.2#3,7,11,13
Section 4.3#1,3,6,9,12,17,21,29,31,37
Section 4.4#3,5,11,13
Homework 6 (Quiz 6)
Section 4.6#3,5,19
Section 4.7#3,5,13,15
Homework 7 (Quiz 7)
Section 7.1#1,21,23,26,37,39,
Section 7.2#1,3,5,15,19,23,31,33,35,36
Homework 8 (Quiz 8)
Section 7.3#2,3,5,11,13,15,17,40,41,43,47,49,53,55,57
Section 7.4#1,3,9,21,25,27
Homework 9 (Quiz 9)
Section 7.5#1,3
Appendix II Matrices#2,3,4,8,11,12,13
Section 8.1#1,7,19,20
Homework (included on Exam 2)
Section 8.2#1,3,7,9,13
Appendix II Matrices#25,26,47,48,49,51,52
Homework 10 (Quiz 10)
Section 8.2#19,21,25,35,37
Homework (included on Final)
Section 8.3#1,3,9,11
Section 8.4#1,9,15,17

Announcements

[03-May-2026] Sample Final

The Final will be given at on Wednesday, May 13, 2026 from 10:15-12:15pm in PE104. It is comprehensive and covers the entire course. I have prepared a sample exam to help you prepare.

[19-Apr-2026] Sample Exam 2

Exam 2 will be given in class Wednesday, April 22. It covers Sections 4.6 up to and including Section 8.2 on our syllabus. I have prepared a sample exam to help you prepare.

[08-Mar-2026] Sample Midterm

The Midterm will be given in class Wednesday, March 11. It covers up to and including Section 4.4 on our syllabus. I have prepared a sample exam to help you prepare.

[18-Feb-2026] Snow Day

Following an assessment of the anticipated overnight weather and road conditions around the University of Nevada, Reno campus, nonessential campus operations and in person classes are suspended today.

[21-Jan-2026] Welcome Spring 2026

I am looking forward to seeing you January 26 starting the first week of class.

In person attendance is mandatory for all computing labs, quizzes, exams and the final.

Grading

     2 Exams                   50 points each
     10 Quizzes                10 points each
     Final                    100 points
    ------------------------------------------
                              300 points total
Exams and quizzes will be interpreted according to the following grading scale:
    Grade        Minimum Percentage
      A                 90 %
      B                 80 %
      C                 70 %
      D                 60 %
The instructor reserves the right to give plus or minus grades and higher grades than shown on the scale if it is believed they are warranted.

Calendar


Jan 21    1.1-1.2     Initial Value Problems
Jan 23    1.2         Existence of a Unique Solution

Jan 26    2.1         Direction Fields
Jan 28    2.2         Separation of Variables (quiz 1)
Jan 30    2.3         Variation of Parameters

Feb 2     2.3         Variation of Parameters
Feb 4     2.4         Exact Equations (quiz 2)
Feb 6     2.5         Solution by Substitution

Feb 9     2.6         Numerical Solutions
Feb 11    9.1         Error Analysis (quiz 3)
Feb 13    9.2         Runge-Kutta Methods

Feb 16    President's Day
Feb 18    4.1.1       Initial-Value and Boundary-Value Problems
Feb 20    4.1.2-4.1.3 Homogeneous and Nonhomogeneous Equations
            
Feb 23    4.2         Reduction of Order
Feb 25    4.3         Constant Coefficients (quiz 4)
Feb 27    4.3         Constant Coefficients

Mar 2     4.4         Superposition Approach
Mar 4     4.6         Variation of Parameters (quiz 5)
Mar 6     4.7         Cauchy-Euler Equations

Mar 9     Review
Mar 11    EXAM 1
Mar 13    7.1         Definition of the Laplace Transform

Mar 16    7.2         Inverse Transform
Mar 18    7.2         Inverse Transform (quiz 6)
Mar 20    7.3         Translation on the s-axis and t-axis

Mar 23    Spring Break
Mar 25    Spring Break
Mar 27    Spring Break

Mar 30    7.4         Additional Operational Properites
Apr 1     7.4         Additional Operational Properites (quiz 7)
Apr 3     7.5         Dirac Delta Function

Apr 6     7.5         Dirac Delta Function
Apr 8     8.1         Systems of Linear First Order Equations (quiz 8)
Apr 10    8.1         Systems of Linear First Order Equations

Apr 13    8.2.1       Distinct Real Eigenvalues
Apr 15    8.2.2       Repeated Eigenvalues (quiz 9)
Apr 17    8.2.3       Complex Eigenvalues

Apr 20    Review
Apr 22    EXAM 2             
Apr 24    8.3         Variations of Parameters

Apr 27    8.3         Variations of Parameters
Apr 29    8.4         Matrix Exponential (quiz 10)
May 1     8.4         Matrix Exponential

May 4     Recitation

May 13    Final Exam at 10:15-12:15pm

Course Policies

Communications Policy

Lectures and classroom activities will held in person. If you wish to set up an appointment for office hours please send me a message through WebCampus.

Late Policy

Students must have an approved university excuse to be eligible for a make-up exam. If you know that you will miss a scheduled exam please let me know as soon as possible.

AI Policy

In this course you are welcome to use generative artificial intelligence/large language model tools (such as ChatGPT, Claude, Gemini, Grok, Perplexity, etc.). Using these tools aligns with the course learning outcomes/student goals for an in-depth understanding of calculus.

Please be aware that many AI companies collect and store personal information. Please do not enter your confidential information as part of a prompt.

Also, please note that some of these large language models may make up or hallucinate information. These tools may reflect misconceptions and biases of specific data. Students are responsible for checking facts, finding reliable sources for, and making a critical examination of any work that is submitted.

Plagiarism

Students are encouraged to work in groups and consult resources outside of the required textbook when doing the homework for this class. Please cite any sources you used to complete your work including Wikipedia, other books, online discussion groups, generative AI such as ChatGPT as well as personal communications. Note that answers obtained from any source should be verified and fully understood for homework to have a positive learning outcome. In all cases your sources need to be cited.

Exams and quizzes, unless otherwise noted, will be closed book, closed notes and must reflect your own independent work.

Plagiarism

Students are encouraged to work in groups and consult resources outside of the required textbook when doing the homework for this class. Please cite any sources you used to complete your work including Wikipedia, other books, online discussion groups, generative AI such as ChatGPT as well as personal communications. Note that answers obtained from any source should be verified and fully understood for homework to have a positive learning outcome. In all cases your sources need to be cited.

Exams and quizzes, unless otherwise noted, will be closed book, closed notes and must reflect your own independent work.

Academic Conduct

Bring your student identification to all exams. Work independently on all exams and quizzes. Behaviors inappropriate to test taking may disturb other students and will be considered cheating. Don't send electronic messages, talk or pass notes with other students during a quiz or exam. Homework may be discussed freely. When taking a quiz or exam don't read notes or books unless explicitly permitted. Sanctions for violations are specified in the University Academic Standards Policy.

If you are unclear as to what constitutes cheating, please consult with me.

Diversity

This course is designed to comply with the UNR Core Objective 10 requirement on diversity and equity. More information about the core curriculum may be found in the UNR Catalog.

Statement on Academic Success Services

Your student fees cover usage of the University Math Center, (775) 784-4433; University Tutoring Center, (775) 784-6801; and University Writing & Speaking Center, (775) 784-6030. These centers support your classroom learning; it is your responsibility to take advantage of their services. Keep in mind that seeking help outside of class is the sign of a responsible and successful student.

Equal Opportunity Statement

The University of Nevada Department of Mathematics and Statistics is committed to equal opportunity in education for all students, including those with documented physical disabilities or documented learning disabilities.

Statement of Disability Services

Any student with a disability needing academic adjustments or accommodations is requested to speak with me or the Disability Resource Center (Pennington Achievement Center Suite 230) as soon as possible to arrange for appropriate accommodations. This course may leverage 3rd party web/multimedia content, if you experience any issues accessing this content, please notify your instructor

Mental Health Support Statement

There are times when you may experience difficulties in life, and you may benefit from seeking help. Mental health services are available to you as a student at no additional cost through Counseling Services at the Pennington Student Achievement Center. This includes same-day in-person and tele mental health initial consultations, brief individual counseling, and group counseling sessions. Limited same-day appointments can be scheduled online via Counseling Services or by calling 775-784-4648. Additional brief drop-in "Let's Talk" student consultations are also available in the Counseling Services Annex located at the southwest corner of Great Basin Hall.

Veteran Statement

Veterans, Reservists, National Guard and military connected family members may wish to check the office of Veteran Services for benefits and support. Besides processing VA educational benefits, the department offers a variety of programs year-round to support student academic and personal success while transitioning to higher education and throughout your educational experience. They welcome inquiries regarding VA benefits and assist in navigating resources, the campus, and in the Reno community.

Statement on Audio and Video Recording

Surreptitious or covert video-taping of class or unauthorized audio recording of class is prohibited by law and by Board of Regents policy. This class may be videotaped or audio recorded only with the written permission of the instructor. In order to accommodate students with disabilities, some students may be given permission to record class lectures and discussions. Therefore, students should understand that their comments during class may be recorded.

Final Exam

The final exams will be held in person at the time listed in the standard schedule of final exams for this section. Namely, the final exam is Wednesday, May 13, 2026 from 10:15-12:15pm in PE104.
Last Updated: Sun Jan 18 02:57:49 PM PST 2026