\(2-x^2=\sqrt{2-x}\left(ĐK:x\le2\right)\)
\(\Leftrightarrow\left(2-x^2\right)^2=\left(\sqrt{2-x}\right)^2\)
\(\Leftrightarrow4-4x+x^2=2-x\)
\(\Leftrightarrow x^2-4x+x+4-2=0\)
\(\Leftrightarrow x^2-3x+2=0\)
\(\Leftrightarrow x^2-x-2x+2=0\)
\(\Leftrightarrow x\left(x-1\right)-2\left(x-1\right)=0\)
\(\Leftrightarrow\left(x-1\right)\left(x-2\right)=0\)
\(\Leftrightarrow\left[\begin{array}{nghiempt}x-1=0\\x-2=0\end{array}\right.\)
\(\Leftrightarrow\left[\begin{array}{nghiempt}x=1\\x=2\end{array}\right.\)
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