# 问题1 1: f = 1 / (e^(-x) + e^x) 2 标签 0: 默认求解器 1: 向前差分 2: 向后差分 3: rk45 ![image-20210117035636815](https://public.veypi.com/img/screenshot/20210117035636.png) ![image-20210117040727886](https://public.veypi.com/img/screenshot/20210117040727.png)