4 Chapter 2, First order equations. Existence and Uniqueness of Solutions of Nonlinear Equations. Section 2.3 Page 60

 4.1 problem 1
 4.2 problem 2
 4.3 problem 3
 4.4 problem 4
 4.5 problem 5
 4.6 problem 6
 4.7 problem 7
 4.8 problem 8
 4.9 problem 9
 4.10 problem 10
 4.11 problem 11
 4.12 problem 12
 4.13 problem 13
 4.14 problem 16
 4.15 problem 18
 4.16 problem 19
 4.17 problem 20(a)