ĐKXĐ: \(x\ge0\)
\(pt\Leftrightarrow2x-4\sqrt{x}+\sqrt{x}-2=7\)
\(\Leftrightarrow2x-3\sqrt{x}-9=0\Leftrightarrow\left(\sqrt{x}-3\right)\left(2\sqrt{x}+3\right)=0\)
\(\Leftrightarrow\sqrt{x}=3\Leftrightarrow x=9\left(tm\right)\)(do \(2\sqrt{x}+3\ge3>0\))
\(\left(2\sqrt{x}+1\right)\left(\sqrt{x}-2\right)=7\)
<=> \(2\sqrt{x}.\sqrt{x}-2\sqrt{x}.2+\sqrt{x}-2=7\)
<=> \(2x-4\sqrt{x}+\sqrt{x}-2=7\)
<=> \(2x-3\sqrt{x}-9=0\)
<=> \(2x-6\sqrt{x}+3\sqrt{x}-9=0\)
<=> \(2\sqrt{x}\left(\sqrt{x}-3\right)+3\left(\sqrt{x}-3\right)=0\)
<=> \(\left(2\sqrt{x}+3\right)\left(\sqrt{x}-3\right)=0\)
<=> \(\left[{}\begin{matrix}2\sqrt{x}+3=0\\\sqrt{x}-3=0\end{matrix}\right.\)
<=> \(\left[{}\begin{matrix}\left(Vô.nghiệm\right)\\x=9\end{matrix}\right.\)
