Posted by haifeng on 2026-06-07 10:39:11 last update 2026-06-07 10:39:11 | Answers (0) | 收藏
\[ t=\frac{\bar{X}_1-\bar{X}_2}{\sqrt{\frac{s_1^2}{n_1}+\frac{s_2^2}{n_2}}} \]
