10 Chapter 3, Second order linear equations, section 3.6, Variation of Parameters. page 190

  10.1 problem 1
  10.2 problem 2
  10.3 problem 3
  10.4 problem 4
  10.5 problem 5
  10.6 problem 6
  10.7 problem 7
  10.8 problem 8
  10.9 problem 9
  10.10 problem 10
  10.11 problem 11
  10.12 problem 12
  10.13 problem 13
  10.14 problem 14
  10.15 problem 15
  10.16 problem 16
  10.17 problem 17
  10.18 problem 20
  10.19 problem 29
  10.20 problem 30
  10.21 problem 31
  10.22 problem 32