\(\Leftrightarrow x^3+3x^2+3x+1-x^3-27=\left(x-3\right)^3-x^3+5x-1+3\left(2x+1\right)^2\)
\(\Leftrightarrow3x^2+3x-26=x^3-9x^2+27x-27-x^3+5x-1+3\left(2x+1\right)^2\)
\(\Leftrightarrow3x^2+3x-26=-9x^2+32x-28+12x^2+12x+3\)
\(\Leftrightarrow3x^2+3x-26=3x^2+44x-25\)
=>-41x=1
hay x=-1/41