Tính: (1/2 x^4 - 1/4 x^3 + x) : (-1/8 x)

$\left(\frac{1}{2}{x}^4-\frac{1}{4}{x}^3+x\right):\left(-\frac{1}{8}x\right)$

$=\frac{1}{2}{x}^4:\left(-\frac{1}{8}x\right)-\frac{1}{4}{x}^3:\left(-\frac{1}{8}x\right)+x:\left(-\frac{1}{8}x\right)$

$=\left(\frac{1}{2}:\frac{-1}{8}\right).\left(x^4:x\right)-\left(\frac{1}{4}:\frac{-1}{8}\right).\left(x^3:x\right)+\left(1:\frac{-1}{8}\right).\left(x:x\right)$

$=\frac{-8}{2}.x^3-\frac{-8}{4}.x^2+\left(-8\right)$ 

= -4x3 + 2x2 - 8.