antifan dau diem danh

nhu kit

\(=\frac{\sqrt{x}\left(\sqrt{x}+3\right)+\sqrt{x}\left(\sqrt{x}-3\right)-\left(3x-9\right)}{\left(\sqrt{x}-3\right)\left(\sqrt{x}+3\right)}\)

\(=\frac{x+3\sqrt{x}+x-3\sqrt{x}-3x+9}{\left(\sqrt{x}-3\right)\left(\sqrt{x}+3\right)}=\frac{-x+9}{x-9}=\frac{-\left(x-9\right)}{x-9}=-1\)

n kit di mi meo ve dau