Because high school mathematics involves functions and integrals, there is no application problem like primary school, and there will be no example of Xiaohong, so there is no Xiaohong in high school mathematics books.
High school mathematics is about sets, logical function sequences, trigonometric functions and vectors. Although I have studied functions and trigonometric functions in junior high school, the abstraction in senior high school has increased and the scope has expanded. Inequality in senior two.