Ta có :
\(\left(\frac{2}{3}xy^2z\right).\left(-3x^2y\right)^2\)
\(=\frac{2}{3}xy^2z.\left(-3\right)^2.\left(x^2\right)^2.y^2\)
\(=\frac{2}{3}xy^2z.9.x^4.y^2\)
\(=\left(\frac{2}{3}.9\right).\left(x.x^4\right).\left(y^2.y^2\right).z\)
\(=6x^5y^4z\)
Chúc bạn học tốt !!!!