Question

Answer 1

\(a,\\ \text{Đ}K\text{X}\text{Đ}:\left\{{}\begin{matrix}x\ge0\\x\ne9\end{matrix}\right.\\ P=\dfrac{x-\sqrt{x}}{x-9}+\dfrac{1}{\sqrt{x}+3}-\dfrac{1}{\sqrt{x}-3}\\ =\dfrac{x-\sqrt{x}+\sqrt{x}-3-\sqrt{x}-3}{\left(\sqrt{x}+3\right)\left(\sqrt{x}-3\right)}\\ =\dfrac{x-\sqrt{x}-6}{\left(\sqrt{x}+3\right)\left(\sqrt{x}-3\right)}\\ =\dfrac{\left(\sqrt{x}-3\right)\left(2+\sqrt{x}\right)}{\left(\sqrt{x}+3\right)\left(\sqrt{x}-3\right)}\\ =\dfrac{2+\sqrt{x}}{\sqrt{x}+3}\)