Chapter 2. Linear homogeneous equations. Section 2.2 problems. page 95

  4.1 problem 49
  4.2 problem 50
  4.3 problem 51
  4.4 problem 52
  4.5 problem 53
  4.6 problem 54
  4.7 problem 55
  4.8 problem 56
  4.9 problem 57
  4.10 problem 58
  4.11 problem 59
  4.12 problem 60