# DE II – HW – S19

All HW is from Fundamentals of Differential Equations, 9th Edition, by Nagle, Saff, and Snider or the identical Fundamentals of Differential Equations with boundary value problems, 7th Edition, by Nagle, Saff, and Snider

• Section 8.1, page 425: 1, 3, 5
• Section 8.2, page 433: 1, 3, 5, 9, 11, 17, 21
• Section 8.3, page 443: 11, 13, 19, 25, 27
• Section 8.4, page 449: 1, 3, 7, 9, 13, 15
• Section 8.5, page 453: 1, 3, 5, 11
• Section 8.6, page 464: 1, 3, 5, 7, 11, 13, 15, 19, 23, 27
• Section 8.7, page 473,: 1-13 odds. On these problems do not find the full series solution, but rather find the indicial equation and the form of the solutions as given by Theorem 7 of this chapter.
• Section 8.8, page 485: 13, 15, 17
• The First Exam takes place Friday, Feb. during class time in the regular classroom. It covers all the hw above. It is closed book, no notes, no calculators. The following list of review problems will give you some idea of what to expect: Chapter review, #1a, 8.2 #4, 8.3 # 14, 8.4 #4 and #8, 8.5 #2 and #6, 8.6 #6, #14, and #26, 8.7 #2 and #8, 8.8 #14,#16, and #18, and this additional problem: Find the power series expansion about zero of the following DE. Your answer should include a formula for the nth coefficient and be a summation, y’ + xy = 0. The solutions to these problems are here exam1_rev_soln. (A correction to 8.7 #2 was added on 2/13) Do not look at the solutions until you have completely solved the problem!
• A sample exam is here samp1. The actual exam could be easier or harder and could have different types of problems. This is only to give you some idea of what the test will look like.

• Section 9.1, page 500: 1, 3, 5
• Section 9.3, page 514: 21, 23, 25
• Section 9.5, page 531: 1, 3, 5, 11, 13, 15
• Section 9.6, page 537: 1, 3, 5, 7, 13
• Section 9.7, page 542: 1, 3, 7, 9
• Section 9.8, page 551: 1, 3, 5, 17, 21. And the two additional problems here: sect9.8_xtra
• Section 10.2, page 570: 15, 17, 19, 21
• Section 10.3, page 584: 9, 11, 13, 28
• Section 10.4, page 591: 5, 7, 11, 13, 17, 19
• The Second  Exam takes place Friday, March 29 during class time in the regular classroom. It covers all the hw above since the last exam. It is closed book, no notes, no calculators. The following list of review problems will give you some idea of what to expect: Chapter review, 9.5 # 12, 14, 20,  9.6 #2, 6, 10.2 #18, 20, 10.3 #10, 10.4 # 8, 12 and these additional problems rev2_xtra. The solutions are here rev2_soln. Some formulas that will be available during the exam are here form. Do not look at the solutions until you have completely solved the problem!