Differential Equations

Math 23 Winter 2018

Homework

Homework reinforces concepts and skills while challenging students to extend what they have learned to other types of problems. Because it is important for students to have this experience, instructors will not solve assigned homework problems during office hours before the due date. We will of course answer questions you may have in approaching problems that give you difficulty. It is therefore essential to begin homework sets early so that you may get help if difficulties do arise. This is especially true for problems that involve programming.

Homework grading policy: Because the goal of homework is to have students work through problems, homework grading is based on both effort and correctness based on the following 10 point scale: 85% or higher = 10; 81-85% = 9; 71-80% = 8; 61-70% = 7; 50-60% = 6; "reasonable effort" = 5; "little or no effort" = 0. Your lowest homework score will be dropped.

Written homework should be turned in to the homework boxes outside of Kemeny 108 by 3:30pm each Wednesday (unless otherwise stated).

No late homework will be accepted.

Please follow the homework submission guidelines.

Cooperation on homework is permitted (and encouraged), but if you work together, do not take any paper away with you--in other words, you can share your thoughts (say on a blackboard), but you have to walk away with only your understanding. In particular, you must write the solution up on your own. Please acknowledge any cooperative work at the end of each assignment.

Assignment Due Date Problems
HW 1 Wednesday January 10 §1.1: #7, 9, 12, 24
§1.2: #5, 12 (Hint: do (b) first), 13
§1.3: #8, 14
§2.1: #15, 17, 30, 33
Also please submit your FERPA waiver.
HW 2 Wednesday January 17 §2.2: #8, 18, 25
§2.3: #2, 4, 8 (Hint: Solve 8 (c) numerically.)
§2.4: #11, 14, 22, 25, 28, 33
§2.5: #4, 12, 15
HW 3 Wednesday January 24 §2.6: #2, 14, 16, 24, 27
§2.7: #3, 17
§8.1: #9, 20
§8.2: #9
§8.3: #9
Use exercise 24 in 2.6 to solve the equation $$(3y^2 + 4xy) + (4xy + 3x^2) \frac{dy}{dx} = 0.$$
HW 4 Wednesday January 31 §3.1: # 11, 12, 16, 22, 23, 27
§3.2: # 10, 19, 22, 27, 34, 39
§3.3: # 1, 5, 11, 20, 26, 35
§3.4: # 6, 13, 21, 28
HW 5 Wednesday February 7 §3.5: # 9, 14, 16, 18, 29, 35
§3.6: # 4, 10, 15, 21, 22, 23, 32
§7.1: # 7, 15
§7.3: # 11, 15, 25
§7.4: # 3, 5, 6
HW 6 Wednesday February 14
§7.5: # 8, 12, 18, 25
§7.6: # 11, 14, 28
§7.8: # 10, 15, 18 (only (a), (b), (c), (d))
HW 7 Wednesday February 21
§7.9: # 2, 4, 11, 14
§6.1 # 2, 14, 24
§6.2 # 16, 26, 29, 32
§6.3 # 18, 20, 25
§6.4 # 8, 17
HW 8 Wednesday February 28
§6.5 # 8, 14, 18
§6.6 # 1, 2, 16, 22
§9.1: # 15, 18, 20, 21
§9.2: # 2, 4, 6, 7, 8, 25
HW 9 Monday, March 5
3:30 pm
§9.3: # 4, 6, 9, 20, 27
§9.4: # 3, 5
§9.5: # 4, 5, 6