\(\left(\frac{4}{5}x^4y^2\right)\left(\frac{5}{9}xy\right)=\left(\frac{4}{5}\cdot\frac{5}{9}\right)\left(x^4x\right)\left(y^2y\right)=\frac{4}{9}x^5y^3\)
\(a,(\frac{4}{5}x^4y^2).(\frac{5}{9}xy)\)
\(=\frac{4}{5}.\frac{5}{9}.x^4.x.y^2.y\)
\(=\frac{4}{9}x^5y^3\)
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