# Math 23Homework Assignments

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General Info.
Term Schedule
Homework Assignments
( January 5th, January 7th, January 10th, January 12th, January 14th, January 18th, January 19th, January 21st, January 24th, January 26th, January 28th, January 31st, February 2nd, February 7th, February 8th, February 9th, February 14th, February 21st, February 25th, February 28th, March 1st, March 3rd )
Lecture Notes
Exam 1 - Information
Exam 2 - Information

The homework assignments on this page are organized by day they are assigned. On many days you will have both a reading assignment, and a problem set. Unless we indicate otherwise, all readings come from your textbook, Elementary Differential Equations and Boundary Value Problems, 6th ed. by Boyce and DiPrima. Furthermore, the current homework assignment (the one due during the next class meeting) will be highlighted by an orange title bar.

Section 1: No HW.

Section 2:

Due at the beginning of class Friday, January 7th.

PROBLEMS: Section 2.5: 6, 9, and 27 (pp 54-57)

Due at the beginning of class Monday, January 10th.

Section 1: [Assignment not yet posted]

Section 2:

PROBLEMS:
Section 2.1: 14, 16, 30 (pp. 23-25)
Section 2.2: 6, 10, 25 (pp. 30-33)
Section 2.3: 7, 12, 23 (pp. 38-40)

Due at the beginning of class Wednesday, January 12th.

Section 1: [Assignment not yet posted]

Section 2:

PROBLEMS:
Section 2.2: #29
Section 2.6: #2

Write out the case for the odd terms from the example today in class.

Supplemental problems
Solution to series problem #4

Due at the beginning of class Friday, January 14th.

Supplemental problems
Solutions to selected problems
Convergent sequence proof example
Comparison test examples
Ratio test examples
Geometric series examples

Due at the beginning of class Tuesday, January 18th.

Supplemental problems

No Homework.

PROBLEMS:
Section 3.1: 1, 2, 5, 10, 17, 18, 21 (pp. 128-129)
Section 3.2: 13 (pg. 138)
Section 3.5: 2, 4, 14 (pg. 159)

PROBLEMS:
Section 3.3: 11 (pp. 144)
Section 3.4: 9, 14, 24 (pg. 150-151)

READING: Sections 11.3 and 11.4 of handout

PROBLEMS: (from in-class handout)
Section 11.3: 1abc, 4, 5, 7 (pp. 638-639)

READING: Sections 11.3 and 11.4 of handout

PROBLEMS: (from in-class handout)
Section 11.4: 1ab, 5a, 7ej (pp. 647-648)

READING: Section 7.2 (review of matrices and determinants)/4.1

PROBLEMS:
Section 3.3: 1,3,4,5,7,12,22,23,27

PROBLEMS:
Section 4.1: 7,8,12,13,14,20abc

Supplemental problems

PROBLEMS:
Section 3.6: 1,3,5,6,12,13,14

Due Wednesday.

PROBLEMS:
Section 3.5: 26,28
Section 3.7: 5,6,10,13,15

Due next Monday.

PROBLEMS:
Section 3.8: 10,11,17

Due next Monday.

PROBLEMS:
Section 3.9: 5, 6, 12
Section 7.2: 14, 15, 18, 22, 23, 24, 26

PROBLEMS:
Section 7.3: 1, 2, 6, 7, 16, 19, 20, 23, 29, 31
[Note: you may need to refer to example 3 in section 7.3 for problems 6 and 7]

PROBLEMS:
Section 7.5: 2, 3, 4, 16
NOTE: We didn't talk a lot about plotting in class, but try doing it for #2. You don't need to draw plots or direction fields for the others, but you should still be able to describe the behavior of solutions as t goes to infinity. You may use a graphing calculator (or maple, if you're really amibitious: I can give you my source code).

Section 7.6: 2, 4, 5, 9
NOTE: Again, plot trajectories and a direction field for #2 only.

Section 7.7: 2, 4, 7
NOTE: No graphs necessary for these.

## Special Instructions

For the following problems from Chapter 3, I would like you to convert the second order equations to systems of first order D.E.'s and solve using the techniques from Chapter 7.

PROBLEMS:
Section 3.1: 4, 8

Section 3.4: 10, 15

Section 10.1: 3

Due Wednesday, March 1st.

PROBLEMS:
Section 10.2: 14, 15, 18

NOTE: Graph sketching is required.
In addition to these problems, I would like for you to verify that is orthogonal to for any choice of m and n, except when m = n (This is equation 6 in section 10.2). When m = n, you should compute the value of their inner product.

Due Friday, March 3rd.

PROBLEMS:
Section 10.3: 3, 6, 10ab

Section 10.4: 8, 10, 15, 16, 22

Section 10.5: 1, 4

PROBLEMS:

Section 10.5: 2, 3, 12abc

### Special Instructions

For problems 2 and 3 in Section 10.5, instead of using the boundary conditions stated in the book, I would like for you to use the boundary conditions u(0,t) = -20, u(40,t) = 20 (L = 40cm). You should explicitly exhibit both the steady-state solution and the transient solution.

Section 10.6: 1abc, 2abc (Note: You do not need to hand in Section 10.6 problems, but you should try them!)

Created on 12 Jul 1998 by A. L. Jones
Modified on 1 Mar 2000 by L. Gariepy.
All graphics created using The GIMP.