(-2x + 2/3 y^2 x-x) * (x^2 2y 2x^3)

$$\\(-2x + \frac{2}{3} y^2 x-x) * (x^2 2y 2x^3)\\\\
=(-2x-x + \frac{2}{3} y^2 x) * (2*2*x^2*x^3*y)\\\\
=(-3x + \frac{2}{3} y^2 x) * (4*x^{2+3}*y)\\\\
=(-3x + \frac{2}{3} y^2 x) * (4x^5y)\\\\
=(4x^5y)(-3x + \frac{2}{3} y^2 x) \\\\
=(4x^5y)(-3x) +(4x^5y)(\frac{2}{3} y^2 x ) \\\\
=-12x^6y +\frac{8}{3} y^3 x ^6 \\\\$$

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