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


