[Toán 8] Giải phương trình

N

nhuquynhdat

$2x^3-12x^2+17x-2=0$

$\leftrightarrow 2x^3-4x^2-8x^2+16x+x-2=0$

$\leftrightarrow 2x^2(x-2)-8x(x-2)+(x-2)=0$

$\leftrightarrow (x-2)(2x^2-8x+1)=0$

$\leftrightarrow x-2=0 (2x^2-8x+1 \ne 0)$

$\leftrightarrow x=2$
 
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