20 Chapter 1, section 1.2. Riccati Equation. subsection 1.2.8-2. Equations containing arbitrary functions and their derivatives.

 20.1 problem 34
 20.2 problem 35
 20.3 problem 36
 20.4 problem 37
 20.5 problem 38
 20.6 problem 39
 20.7 problem 40
 20.8 problem 41
 20.9 problem 42