This is a tutorial book about problem sets. Mathematics 660 for Postgraduate Entrance Examination is a book published by China Railway Publishing House in June 2008. This is a tutorial book with problem sets suitable for intensive use. The examples in this book are selected from important documents at home and abroad. Therefore, Postgraduate Mathematics 660 is the meaning of a book. Unified-National-Postgraduate Admission-Examination, referred to as "Postgraduate Entrance Examination".