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vansang02121998

$\frac{6x^3+7x^2+5x+2}{2x^2+x+1}=x-5$

$\Rightarrow 6x^3+7x^2+5x+2=(x-5)(2x^2+x+1)$

$\Leftrightarrow 6x^3+7x^2+5x+2=2x^3-9x^2-4x-5$

$\Leftrightarrow 4x^3+16x^2+9x+7=0$

$\Leftrightarrow 4x^3+14x^2+2x^2+7x+2x+7=0$

$\Leftrightarrow 2x^2(2x+7)+x(2x+7)+2(2x+7)=0$

$\Leftrightarrow (2x+7)(2x^2+x+2)=0$

$\Leftrightarrow x=\frac{-7}{2}$
 
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