User:Laxori666

Random maths:

$$\sum_{i=1}^n a_i\mu_i$$

$$\sum_{i=1}^n \sum_{j=1}^m a_i b_j \operatorname{Cov}(Y_i, X_j)$$

$$n \left(\frac{r}{N}\right) \left(\frac{N - r}{N}\right) \left(\frac{N - n}{N - 1}\right)$$

$$\operatorname{E}(g(Y_1) | Y_2 = y_2) = \int_{-\infty}^{\infty}g(y_1)f(y_1|y_2)dy_1$$

$$\int_{-\infty}^\infty x \frac{n!}{(n-1)!} (1 - F(x))^{n-1} f(x) dx = \int_{-\infty}^\infty xf(x)dx$$

$$\frac{(n-1)S^2}{\sigma^2}$$ $$S^2$$ $$\Chi^2$$ $$\mu$$ $$\sigma^2$$

$$\sqrt{n}\left(\frac{\bar{Y} - \mu}{S}\right)$$

$$\frac{\left(\bar{X} - \bar{Y}\right) - \left(\mu_1 - \mu_2\right)}{\sqrt{\frac{\sigma_1^2}{n_1} + \frac{\sigma_2^2}{n_2}}}$$

$$\frac{\left(\bar{X} - \bar{Y}\right) - \left(\mu_1 - \mu_2\right)}{\sqrt{\frac{S_p^2}{n_1} + \frac{S_p^2}{n_2}}}$$

$$\bar{Y}$$

$$N(\mu, \sigma^2)$$

$$N(\mu_1, \sigma_1^2)$$ $$N(\mu_2, \sigma_2^2)$$