\begin{pspicture}(-5,-5)(5,5)
\psset{xunit=1 cm, algebraic=true}
\psaxes{->}(0,0)(-5,-5)(5,5)

% Trouver antécédents
\psline[linecolor=green,linewidth=1pt]{-}(0,1)(1,1)
\psline[linecolor=green,linewidth=1pt]{-}(1,1)(1,0)
\psline[linecolor=green,linewidth=1pt]{-}(0,0.5)(2,0.5)
\psline[linecolor=green,linewidth=1pt]{-}(2,0.5)(2,0)
\psline[linecolor=green,linewidth=1pt]{-}(0,0.25)(4,0.25)
\psline[linecolor=green,linewidth=1pt]{-}(4,0.25)(4,0)

\psline[linecolor=green,linewidth=1pt]{-}(0,-1)(-1,-1)
\psline[linecolor=green,linewidth=1pt]{-}(-1,-1)(-1,0)
\psline[linecolor=green,linewidth=1pt]{-}(0,-0.5)(-2,-0.5)
\psline[linecolor=green,linewidth=1pt]{-}(-2,-0.5)(-2,0)
\psline[linecolor=green,linewidth=1pt]{-}(0,-4)(-0.24,-4)
\psline[linecolor=green,linewidth=1pt]{-}(-0.25,-4)(-0.25,0)

% Images
\psline[linecolor=red,linewidth=1.5pt]{-}(0,1)(0,-4.8)

%antécédents
\psline[linecolor=red,linewidth=2pt]{-}(1,0)(4.8,0)
\psline[linecolor=red,linewidth=2pt]{-}(0,0)(-4.8,0)

% la fonction inverse
\psplot[linecolor=black,linewidth=1.5pt]{-5}{-0.2}{1/x}
\psplot[linecolor=black,linewidth=1.5pt]{0.2}{5}{1/x}

\end{pspicture}
