Useful. According to the inquiry of Tik Tok app, it can be seen that Ge Yong Zhao Dashu was founded by a group of teachers who are proficient in teaching and love education. It is not only the stage for teachers, but also the stage for students themselves. Here, students can get a perfect domestic teaching experience and improve themselves quickly. With superb teaching ability and advanced scientific and technological means, Ge Yong Mathematics enables students in China, especially children in underdeveloped areas, to get a better education at a more favorable price and in a more convenient way. Therefore, Ge Yong's big book is useful.