\[\left( 5\frac{1}{3}\text{\ xy} \right)\left( \frac{3}{8}x^{3}y^{2} \right) - 2x^{2}y^{2}\left( x^{2}y - xy \right) + x^{3}y^{3} =\]
\[= \frac{16}{3}xy \cdot \frac{3}{8}x^{3}y^{2} - 2x^{4}y^{3} + 2x^{3}y^{3} + x^{3}y^{3} =\]
\[= 2x^{4}y^{3} - 2x^{4}y^{3} + 3x^{3}y^{3} = 3x^{3}y^{3}\]
\[(шестая\ степень)\]