\(=\dfrac{9}{4}-\left[\dfrac{1}{2}\times\dfrac{1}{2}-\dfrac{\sqrt{81}}{3}\right]\\ =\dfrac{9}{4}-\left(\dfrac{1}{4}-\dfrac{9}{3}\right)\\ =\dfrac{9}{4}-\left(\dfrac{1}{4}-3\right)\\ =\dfrac{9}{4}-\left(\dfrac{1-3\times4}{4}\right)\\ =\dfrac{9}{4}-\left(-\dfrac{11}{4}\right)\\ =\dfrac{9}{4}+\dfrac{11}{4}\\ =\dfrac{9+11}{4}\\ =\dfrac{20}{4}\\ =5\)
\(=\dfrac{9}{4}-[\dfrac{1}{4}-\dfrac{9.1}{3}]\)
\(=\dfrac{9}{4}-[\dfrac{1}{4}-\dfrac{9}{3}]\)
\(=\dfrac{9}{4}--\dfrac{11}{4}\)
\(=5\)