Bài 2:
a) \(P=\left(\dfrac{2\sqrt{x}-4}{x-4\sqrt{x}+4}-\dfrac{\sqrt{x}-1}{x-1}\right):\dfrac{\sqrt{x}+4}{x-2\sqrt{x}}\) (ĐK: \(x\ne4,x\ne1,x>0\))
\(P=\left[\dfrac{2\left(\sqrt{x}-2\right)}{\left(\sqrt{x}-2\right)^2}-\dfrac{\sqrt{x}-1}{\left(\sqrt{x}-1\right)\left(\sqrt{x}+1\right)}\right]:\dfrac{\sqrt{x}+4}{\sqrt{x}\left(\sqrt{x}-2\right)}\)
\(P=\left(\dfrac{2}{\sqrt{x}-2}-\dfrac{1}{\sqrt{x}+1}\right):\dfrac{\sqrt{x}+4}{\sqrt{x}\left(\sqrt{x}-2\right)}\)
\(P=\dfrac{2\left(\sqrt{x}+1\right)-\left(\sqrt{x}-2\right)}{\left(\sqrt{x}-2\right)\left(\sqrt{x}+1\right)}:\dfrac{\sqrt{x}+4}{\sqrt{x}\left(\sqrt{x}-2\right)}\)
\(P=\dfrac{2\sqrt{x}+2-\sqrt{x}+2}{\left(\sqrt{x}-2\right)\left(\sqrt{x}+1\right)}\cdot\dfrac{\sqrt{x}\left(\sqrt{x}-2\right)}{\sqrt{x}+4}\)
\(P=\dfrac{\sqrt{x}+4}{\left(\sqrt{x}-2\right)\left(\sqrt{x}+1\right)}\cdot\dfrac{\sqrt{x}\left(\sqrt{x}-2\right)}{\sqrt{x}+4}\)
\(P=\dfrac{\sqrt{x}}{\sqrt{x}+1}\)
b) \(P=\dfrac{3}{4}\) khi:
\(\dfrac{\sqrt{x}}{\sqrt{x}+1}=\dfrac{3}{4}\)
\(\Leftrightarrow4\sqrt{x}=3\sqrt{x}+3\)
\(\Leftrightarrow4\sqrt{x}-3\sqrt{x}=3\)
\(\Leftrightarrow\sqrt{x}=3\)
\(\Leftrightarrow x=9\left(tm\right)\)
giúp e vs ạ ;-;
giúp e vs ạ :<