\psset{xunit=1cm, yunit=1cm}
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\psset{plotpoints=200}
\psaxes[ticks=noticks,linewidth=0.5pt,linecolor=SlateGrey]{->}(0,0)(-2.2,-0.3)(2.2,3.5) %Mittelpunkt (linke Seite x,y 3/4 Quad) (rechte Seite x,y)


\psplot[linecolor=blue]{-1.7320508075688772935}{1.7320508075688772935}{3 x x mul sub}
\psframe[fillstyle=vlines,linecolor = red, hatchcolor=red](-1,0)(1,2)
%\psplot[linecolor=red]{1}{2.5}{x 1 sub 2 exp}


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%\rput[c](1,-0.25){$e$}
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\psline[linecolor=SlateGray,linewidth=0.5pt](-.1,3)(.1,3)
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%\psline[linecolor=blue,linewidth=0.2pt,linestyle=dashed](1,1.5)(1,0)
%\psline(0,0)(4,3)
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%%\psplot[linecolor=yellow]{0.01}{1}{1 x div}
%\rput[c](1.5,-0.1){$x$}
%\rput[c](-0.2,1.8){$y$}

\end{pspicture}%}
%%http://sites.inka.de/picasso/latex.html


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