Posted by haifeng on 2025-09-30 23:07:16 last update 2025-09-30 23:07:16 | Answers (0) | 收藏
求下列函数的间断点并判断间断点的类型.
1. $f(x)=\begin{cases}x, & x\text{为有理数},\\ -x, & x\text{为无理数}.\end{cases}$
