Ta có: \(\dfrac{2}{3}x^2yz\cdot\left(-3xy^2\right)\)
\(=\left(-\dfrac{2}{3}\cdot3\right)\cdot\left(x^2\cdot x\right)\cdot\left(y\cdot y^2\right)\cdot z\)
\(=-2x^3y^3z\)
`(2/3x^2.y.z).(-3x.y^2)`
`=-3.(2/3).x^2.y.z.x.y^2`
`=-1.x^{2+1}.y^{2+1}.z`
`=-x^3y^3z`