Tính một cách hợp lí. 2 3/5.(-2/3) - 2 1/3.(-2/3) + (2/3)^2

\[2\frac{3}{5}.\left( { - \frac{2}{3}} \right) - 2\frac{1}{3}.\left( { - \frac{2}{3}} \right) + {\left( {\frac{2}{3}} \right)^2}\]= \[ - \frac{2}{3}.\left( {2\frac{3}{5} - 2\frac{1}{3} - \frac{2}{3}} \right)\]= \[ - \frac{2}{3}.\left( { - \frac{2}{5}} \right)\]= \[\frac{4}{{15}}\].