\(a,27x^3+27x^2+9x+1=\left(3x\right)^3+3.\left(3x\right)^2.1+3.3x.1^2+1^3=\left(3x+1\right)^3\)\(b,8x^3+12x^2+6x+1=\left(2x\right)^3+3.\left(2x\right)^2.1+3.3x.1^2+1^3=\left(2x+1\right)^3\)
\(a)27x^3+27x^2+9x+1=(3x+1)^3\)
\(b)8x^3+12x^2+6x+1=(2x+1)^3\)