вот держи......................

[tex]3x^4-6x^3+9x^5=3x^3(x-2+3x^2) \Large \textcircled{\raisebox{1pt} {\normalsize\hspace =}}\\\\3x^2+x-2=0\\D=1+24=25=5^2\\\\x_{1,2}=\dfrac{-1\pm5}{6}=\bigg[^\bigg{-1}_\bigg{\dfrac{2}{3} } = > 3x^2+x-2=(x+1)(x-\dfrac{2}{3}) \\\\\Large \textcircled{\raisebox{1pt} {\normalsize\hspace =}}3x^3(x+1)(x-\dfrac{2}{3})[/tex]