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$pt\Leftrightarrow (x+2)^3+2\sqrt{(x+2)^3}+1=9x^2+18x+9=>$$(\sqrt{x+2)^3}+1)^2=(3x+3)^2$
$=>\sqrt{(x+2)^3}=3x+2=>x^3-3x^2+4=0=>(x-2)(x^2-x-2)=0$
$=>x=2$ hoặc $x=-1$(loại)
hoặc $\sqrt{(x+2)^3}=-4-3x=>\begin{cases}x^3-3x^2-12x-8=0 \\ x\in[-2;-\frac43] \end{cases}=>...$
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