Posted by haifeng on 2021-12-18 23:08:12 last update 2021-12-18 23:08:12 | Answers (0) | 收藏
设 $f(x)=\int_0^x \frac{\ln(1-t)}{t}\mathrm{d}t$ 定义于 $(-1,1)$ 内, 证明: $f(x)+f(-x)=\frac{1}{2}f(x^2)$.
