a) ĐKXĐ: \(x\ge3\)
\(pt\Leftrightarrow\sqrt{x-3}-10\sqrt{x-3}+6\sqrt{x-3}=-6\)
\(\Leftrightarrow3\sqrt{x-3}=6\Leftrightarrow\sqrt{x-3}=2\)
\(\Leftrightarrow x-3=4\Leftrightarrow x=7\left(tm\right)\)
b) ĐKXĐ: \(x\ge3\)
\(pt\Leftrightarrow\sqrt{x-3}-2\sqrt{\left(x-3\right)\left(x+3\right)}=0\)
\(\Leftrightarrow\sqrt{x-3}\left(1-2\sqrt{x+3}\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x-3=0\\2\sqrt{x+3}=1\end{matrix}\right.\)\(\Leftrightarrow\left[{}\begin{matrix}x=3\left(tm\right)\\\sqrt{x+3}=\dfrac{1}{2}\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}x=3\\x+3=\dfrac{1}{4}\end{matrix}\right.\)\(\Leftrightarrow\left[{}\begin{matrix}x=3\\x=-\dfrac{11}{4}\left(ktm\right)\end{matrix}\right.\)
