B = \(\frac{x\sqrt{x - 3}}{x - 2\sqrt{x - 3}} - \frac{\sqrt{x + 3}}{2(3 - \sqrt{2})}\) \(\Rightarrow\) \(x = 3\) 1) Tìm \(x \in \mathbb{R}\) và \(B\) 2) Tìm \(x \in \mathbb{R}^3A \in \mathbb{R}\) 3) Tìm min \(B\)