Higher********

This book is quite comprehensive and feels like a "mathematical dictionary". I remember one time my sister couldn't solve a linear algebra question, so I explained it to her based on the knowledge points in this book, and she understood it instantly. Moreover, the content in this book is explained in detail, just like my uncle, who is not very educated, but he can understand it after reading this book. What I like most is the matrix part, it is very helpful for me when planning the route for express delivery!