tìm x 1)8x^3-12x^2+6x-1 2)x^3-6x^2+12x-8=27 3)x^2-8x+16=5(4-x)^3 4)(2-x)^3=6x(x-2) 5)(x+1)^3-(x-1)^3-6(x-1)^2=-10 6)(3-x)^3-(x+3)^3=36x^2-54x

1,
$\displaystyle  \begin{array}{{>{\displaystyle}l}}
8x^{3} -12x^{2} +6x-1=0\\
\Leftrightarrow ( 2x-1)^{3} =0\\
\Rightarrow x=\frac{1}{2}
\end{array}$
2,
$\displaystyle  \begin{array}{{>{\displaystyle}l}}
x^{3} -6x^{2} +12x-8=27\\
\Leftrightarrow x^{3} -5x^{2} -x^{2} +5x+7x-35=0\\
\Leftrightarrow ( x-5)\left( x^{2} -x+7\right) =0\\
\Leftrightarrow ( x-5)\left(\left( x-\frac{1}{2}\right)^{2} +\frac{27}{4}\right) =0\\
\Rightarrow x=5
\end{array}$
3,
$\displaystyle  \begin{array}{{>{\displaystyle}l}}
x^{2} -8x+16=5( 4-x)^{3}\\
\Leftrightarrow x^{2} -8x+16=5\left( 64-48x+12x^{2} -x^{3}\right)\\
\Leftrightarrow 5x^{3} -59x^{2} +232x-304=0\\
\Leftrightarrow 5x^{3} -20x^{2} -39x^{2} +156x+76x-304=0\\
\Leftrightarrow ( x-4)\left( 5x^{2} -39x+76\right) =0\\
\Leftrightarrow ( x-4)\left( 5x^{2} -20x-19x+76\right) =0\\
\Leftrightarrow ( x-4)( x-4)( 5x-19) =0\\
\Rightarrow x=4,x=\frac{19}{5}
\end{array}$