\(\left[\left(\dfrac{-2}{3}\right)^8:\left(\dfrac{-2}{3}\right)^6+\dfrac{2}{3}\right]:\left(-1\dfrac{2}{3}\right)+\left(2\dfrac{38}{45}\right)^0.\sqrt{\dfrac{9}{16}}\)
\(=\left[\left(\dfrac{-2}{3}\right)^{8-6}+\dfrac{2}{3}\right]:\dfrac{-5}{3}+1.\dfrac{3}{4}\)
\(=\left[\left(\dfrac{-2}{3}\right)^2+\dfrac{2}{3}\right]:\dfrac{-5}{3}+1.\dfrac{3}{4}\)
\(=\left[\dfrac{4}{9}+\dfrac{2}{3}\right]:\dfrac{-5}{3}+1.\dfrac{3}{4}\)
\(=\left[\dfrac{4}{9}+\dfrac{6}{9}\right]:\dfrac{-5}{3}+1.\dfrac{3}{4}\)
\(=\dfrac{10}{9}.\dfrac{-3}{5}+1.\dfrac{3}{4}\)
\(=\dfrac{-2}{3}+1.\dfrac{3}{4}\)
\(=\dfrac{-2}{3}+\dfrac{3}{4}\)
\(=\dfrac{-8}{12}+\dfrac{9}{12}\)
\(=\dfrac{1}{12}\)
