(x^2-2x)^2+3x^2-6x=-2

x².(x-2)²+3x(x-2)=-2
x(x-2)(x²-2x+3)=-2
(x-1)².(x²-2x+3)-x²+2x-3=-2
(x-1)².(x²-2x+3)-x²+2x-1=0
(x-1)².(x²-2x+3)-(x-1)²=0
(x-1)².(x²-2x+3-1)=0
\(\left[ \begin{array}{l}x-1=0\\x^{2} -2x+2=0\end{array} \right.\)=> \(\left[ \begin{array}{l}x=1\\(x-1)^{2}+1=0(Loại)\end{array} \right.\) 
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