18 Chapter 1, section 1.2. Riccati Equation. subsection 1.2.7-3. Equations containing arctangent.

 18.1 problem 29
 18.2 problem 30
 18.3 problem 31
 18.4 problem 32
 18.5 problem 33
 18.6 problem 34
 18.7 problem 35
 18.8 problem 36