Question

Answer 1

a: \(P=\dfrac{\sqrt{x}-4+3\sqrt{x}}{\left(\sqrt{x}-2\right)\cdot\sqrt{x}}:\dfrac{x-4-x}{\sqrt{x}\left(\sqrt{x}-2\right)}\)

\(=\dfrac{4\left(\sqrt{x}-1\right)}{\sqrt{x}\left(\sqrt{x}-2\right)}\cdot\dfrac{\sqrt{x}\left(\sqrt{x}-2\right)}{-4}\)

\(=-\sqrt{x}\left(\sqrt{x}-1\right)\)

b: Để \(P=3x-3\sqrt{x}\) thì \(-x+\sqrt{x}-3x+3\sqrt{x}=0\)

\(\Leftrightarrow-4x+4\sqrt{x}=0\)

\(\Leftrightarrow\left[{}\begin{matrix}x=0\left(loại\right)\\x=1\left(nhận\right)\end{matrix}\right.\)