8.9 Chapter 2. Second order differential equations. Section 2.2.2. Equal roots, reduction of order. Excercises page 149

8.9.1 problem 1
8.9.2 problem 2
8.9.3 problem 3
8.9.4 problem 4
8.9.5 problem 6
8.9.6 problem 7
8.9.7 problem 10
8.9.8 problem 11
8.9.9 problem 12
8.9.10 problem 13
8.9.11 problem 14
8.9.12 problem 15
8.9.13 problem 16
8.9.14 problem 17
8.9.15 problem 19
8.9.16 problem 20