Yan Chao: public information is limited, and at present only one work is known, Higher Mathematics (Volume 1), commonly classified under examinations. Judging from this attribution and the work itself, Yan Chao appears to be one of the authors involved in compiling textbooks or exam-preparation materials for higher mathematics, aimed at the study and examination needs of basic university mathematics courses. Higher Mathematics (Volume 1) usually covers functions, limits, derivatives and integrals; it is an important introductory course for students in science, engineering and economics or management, and a required part of the mathematics entrance examination for postgraduate study. Books of this kind therefore tend to stress a complete knowledge system, well-targeted examples and exercises, and clear exposition. Given the limited material, Yan Chao's personal background, institutional affiliation and writing career cannot be confirmed, and no other works or academic activities are recorded. Readers choosing this work may judge it by edition, intended audience and examination requirements.
