21 Chapter 1, section 1.2. Riccati Equation. subsection 1.2.9. Some Transformations

21.1 problem 1
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21.3 problem 3
21.4 problem 4
21.5 problem 5
21.6 problem 6
21.7 problem 7
21.8 problem 8
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21.10 problem 10
21.11 problem 11
21.12 problem 12
21.13 problem 13
21.14 problem 14