Johannes Brust (Instr.)Zhaolong Han (TA)
Office/student hrs:Office/student hrs:
F:4p-5p (remote)T,R: 5p-6:30p (remote)
W:4p-5p (APM 6422)TBD

Welcome to Math 20D (Lecture D, Winter 2022)

This page supplements materials to ``Introduction to Differential Equations''

Math 20D is a combination of numerical and analytic methods for ordinary differential equations. As such this class involves a valuable amount of practical computations. One may use the materials to further learn about differential equations with many variables (partial differential equations) or even as tools to numerically solve problems from research, industry and applications accross a variety of different subjects.

Memo to the student:

Remember, this class is here to help succeed in learning the subject.

  • Homework problems will help prepare for Quiz and Final questions
  • •Being active in Lecture, Discussion and office hours will help to learn
  • •Ask for help when feeling stuck


Jan 1 • Weeks 1&2 are remote (at least until Wed. Jan 17). According to campus recommendation class may transition to in-person after this period.


All times in Pacific Time

Lectures: MWF, 3p-3:50p in PCYNH 109 (remote initially)

Discussions: M (remote initially)

D01: 4p-4:50p (CENTR 217A)
D02: 5p-5:50p (CENTR 217A)
D03: 7p-7:50p (WLH 2114)
D04: 8p-8:50p (HSS 1305)


(Note: Schedule and policies may be updated throughout the quarter)

Remember: Remotely: Midterms, quizzes and final

To access lectures notes use
the UCSD "AD username" (e.g., jjbrust) and "Student ID" (e.g., A1234567)

Week Lect.DateTopicNotes
11Mon, Jan 03, 22Intro. & Sec. 1.1 [nts],[pdcst.1],[pdcst.2]
12Wed, Jan 05, 22Secs. 1.2 & 2.2[nts],[pdcst.]
13Fri, Jan 07, 22Sec. 2.3[nts],[pdcst.1],[pdcst.2]
24Mon, Jan 10, 22Sec. 2.4[nts],[pdcst.1],[pdcst.2]
25Wed, Jan 12, 22Sec. 2.5[nts],[pdcst.1],[pdcst.2]
26Fri, Jan 14, 22Sec. 4.2[nts],[pdcst.1],[pdcst.2]
37Mon, Jan 17, 22MLK Holiday
38Wed, Jan 19, 22Sec. 4.3[nts],[pdcst.1],[pdcst.2]
39Fri, Jan 21, 22Sec. 4.4 [nts],[pdcst.1],[pdcst.2]
410Mon, Jan 24, 22Sec. 4.4[nts],[pdcst.1],[pdcst.2]
411Wed, Jan 26, 22Sec. 4.5[nts],[pdcst.1],[pdcst.2]
412Fri, Jan 28, 22Sec. 4.5
513Mon, Jan 31, 22Sec. 4.6 Quiz 1
514Wed, Feb 02, 22Sec. 4.7
515Fri, Feb 04, 22Sec. 4.7
616Mon, Feb 07, 22Sec. 7.2
617Wed, Feb 09, 22Sec. 7.3
618Fri, Feb 11, 22Sec. 7.4
719Mon, Feb 14, 22Sec. 7.4
720Wed, Feb 16, 22Sec. 7.5
721Fri, Feb 18, 22Sec. 7.6 Quiz 2
822Mon, Feb 21, 22Presidents' Holiday
823Wed, Feb 23, 22Sec. 7.8
824Fri, Feb 25, 22Sec. 7.9
925Mon, Feb 28, 22Sec. 8.2
926Wed, Mar 02, 22Sec. 8.3
927Fri, Mar 04, 22 Sec. 9.1 Quiz 3
1028Mon, Mar 07, 22Sec. 9.5
1029Wed, Mar 09, 22Sec. 9.3
1030Fri, Mar 11, 22Sec. 9.6
1131Mon, Mar 14, 22TBD & review
1132Wed, Mar 16, 22Final Exam (3:00p-5:59p)


Textbook:Fundamentals of Differential Equations (9th ed.),
R.K. Nagle, E.B. Saff and A.D. Snider
Content:We will cover relevant parts of chapters 1,2,4,7,8 and 9
Homework:We use [MyMathLab] for graded Homework and
ungraded ("paper-and-pen") practice Homework from this website
Assessment:All exams/quizzes remote via Gradescope (Pacific Times)
Quizzes available for 24 hours (spanning two days)
Quiz 1 (start: M. Jan. 31, 12pm -- end: Tu. Feb. 1st, 12pm)
Quiz 2 (start: F. Feb. 18, 12pm -- end: Sat. Feb. 19, 12pm)
Quiz 3 (start: F. Mar. 04, 12pm -- end: Sat. Mar. 05, 12pm)
Final (Wed. Mar. 16, 3:00pm -- 5:59am),
(Content: comprehensive)


Weighted final scores from the best of two approaches:

30% Homework + 20% Quizzes + 10% Matlab (5% HW & 5% Quiz) + 40% FinalOR
30% Homework + 30% Quizzes + 10% Matlab (5% HW & 5% Quiz) + 30% Final

Letter grades from weighted final scores and the best of two options

  • (Option A):
  •  A+   A   A-   B+   B   B-   C+   C   C-   D   F 
     97   93   90   87   83   80   77   73   70   60   60> 

  • (Option B):
  • A curve where the median corresponds to B-/C+



Canvas (Course page)
Gradescope (Examination system)
Piazza (Portal to ask questions)
Matlab M20D (Matlab part of the course)
MyMathLab (Online Homework System)


Homework is a very important part of the course and in order to fully master the topics it is essential that you work carefully on every assignment and try your best to complete every problem. We will have two different kinds of homework assignments in this class: online homework (which will be graded) and "paper-and-pen" homework (which will not be graded).

Instructions (homework):

• Online homework will be assigned through MyMathLab.
• Your total homework score will be based on the total possible homework points available; no homework assignment scores will be dropped at the end of the quarter.
• The "paper-and-pen" homework assignments will be announced on this webpage. These assignments will not be turned in and will not be graded; they are for additional practice.

("Paper-and-pen" problems) Due (not graded)
Homework 1 Sec 1.1: 1,3,6,7,10,14
Sec 1.2: 2,3,12,13,18,20
Sec 2.2: 2,4,6,8,13,17,20,25,27,30
Sec 2.3: 3,5,7,8,10,15,17,25,31,35
Jan 14
Homework 2
Sec 2.4: 2, 4, 6, 8, 13, 17, 20, 25, 29
Sec 2.5: 3, 5, 7, 8, 10, 13
Jan 21
Homework 3 Sec 4.2: 2,3,6,8,13,17,20,25,33
Sec 4.3: 1,4,7,8,10,13,17,19,23,27
Sec 4.4: 2,4,7,8,10,13,18,20,21
Jan 28
Homework 4
Homework 5
Homework 6
Homework 7
Homework 8
Homework 9


Please notice that outside factors, including the need for a certain grade for admission/retention in any academic program, scholarship or transfer credit, graduation requirements or personal desire for a specific grade DO NOT appear in the determination of course grades. Effort, improvement, class attendance and participation will all dramatically improve your grade in the course in that they will allow you to do well on exams, and the final exam. They will NOT, however, actively participate in the calculation of course grades.

Accommodations: Students requesting accommodations and services due to a disability for this course are asked to provide a current Authorization for Accommodation (AFA) letter issued by the Office for Students with Disabilities (OSD), prior to eligibility for requests. Receipt of AFAs in advance is necessary for appropriate planning for the provision of reasonable accommodations. OSD Academic Liaisons also need to receive current AFA letters. Students can find department-specific information on exam accommodations on the following Math Department webpage:

    Academic Dishonesty:  Academic dishonesty is considered a serious offense at UCSD.  Students caught cheating will face an administrative sanction which may include suspension or expulsion from the university.  It is in the student's very best interest to maintain academic integrity. (Click here for more information.)