\[\boxed{\mathbf{999}\mathbf{.}}\]
\[1)\ y = (x - 1)^{2},\ ось\ Ox;\ \ \ x = 2:\]
\[2)\ y = 2x - x^{2};\ ось\ Ox:\]
\[3)\ y = \frac{2}{x};\ ось\ \text{Ox};\ \ x = 1;\ \ x = 4:\]
\[4)\ y = \sqrt{x};\ \ ось\ \text{Ox};\ \ x = 4:\]