\begin{tikzpicture}
\begin{axis}[width=10cm,height=10cm,xmin=-1,xmax=5, ymin=-5,ymax = 10,
xtick={-2,-1,...,5},
ytick={-5,0,...,10},
minor xtick={-2,-1.5,...,5},
minor ytick={-5,-4,...,10}]
\addplot[domain=0:2,samples=201,blue,line width=2pt,name path=A]{1*x^3-3*x^2+4*x};
\addplot[domain=0:2,samples=201,blue,line width=2pt,name path=B]{3*x^2-4*x};
\addplot[domain=-3:5,samples=201,black,line width=1pt,name path=C]{1*x^3-3*x^2+4*x};
\addplot[domain=-3:5,samples=201,black,line width=2pt,name path=D]{3*x^2-4*x};