\(y=\left(x^2-\dfrac{2}{x}\right)^3\)
=>\(y'=3\cdot\left(x^2-\dfrac{2}{x}\right)^2\cdot\left(x^2-\dfrac{2}{x}\right)'\)
=>\(y'=3\left(x^2-\dfrac{2}{x}\right)^2\cdot\left(2x-2\cdot\dfrac{-1}{x^2}\right)\)
=>\(y'=3\left(x^2-\dfrac{2}{x}\right)^2\cdot\left(2x+\dfrac{2}{x^2}\right)\)