“习题在数学教学中有着特殊重要的作用。没有必要的、恰当的练习,学生就不可能掌握所学的基础知识,更不用说将知识转化为能力”。典型习题的特色更为显著,如体现典型的解题方法、技巧;上升为公式、定理或法则后,有广泛的应用;纵向深化,有引伸或推广的潜在条件;横向扩展,综合代数、三角、几何等内 “The exercises have a special important role in mathematics teaching. Without the necessary and appropriate practice, students cannot master the basic knowledge they have learned, let alone transform knowledge into competence.” The features of typical exercises are more prominent, such as embodying typical problem-solving methods and techniques; after being raised to formulas, theorems, or rules, there are wide applications; longitudinal deepening, potential conditions for extension or promotion; horizontal expansion, comprehensive algebra, and triangular , Geometry, etc.