\(a,\left(x+3\right)^3=x^3+9x^2+27x+27\\ b,\left(\dfrac{1}{2}-x\right)^3=\dfrac{1}{8}-\dfrac{3}{4}x+\dfrac{3}{2}x^2-x^3\\ c,\left(2x-y^2\right)^3=8x^3-12x^2y^2+6xy^4-y^6\\ d,\left(2x-\dfrac{y^2}{x}\right)^3=8x^3-\dfrac{12x^2y^2}{x}+\dfrac{6xy^4}{x^2}-\dfrac{y^6}{x^2}\\ =8x^3-12xy^2+6y^4-\dfrac{y^6}{x^2}\)