31.Comparative Rate of Functions and Inde-pendent Variables

32.Derivatives

33.Newton’s Integrals and Riemann’s Integrals

34.Differential Equation

35.The Orthogonal Trajectories

36.Variations （Ⅰ）

37.Variations （Ⅱ）

38.Variations （Ⅲ）

39.The Distribution of Prime Numbers

40.Comments on the Zeta Function

41.Fermat’s Equation

42.Constructions by Ruler and Compass

43.Number （Ⅰ）

44.Number （Ⅱ）

45.Sets， Systems， and Groups

46.Concepts of Sets （Ⅰ）

47.Concepts of Sets （Ⅱ）

48.On Cantor’s Definition of Set

49.The Upper and Lower Boundaries of a Linear Set of Points

50.Bounded Set and Unbounded Set

51.Denumerable Sets （Ⅰ）

52.Denumerable Sets（Ⅱ）

53.The Continuum of Real Numbers （Ⅰ）

54.The Continuum of Real Numbers （Ⅱ）

55.The Concept of Cardinal Number （Ⅰ）

56.The Concept of Cardinal Number （Ⅱ）

57.Definition of Order

58.Property of Order-Relation

59.Ordered Sets （Ⅰ）

60.Ordered Sets （Ⅱ）