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 %\psgrid[griddots=10,gridlabels=0pt, subgriddiv=0]
 
 %%%%%%%%%%%%%%%%%%%%%%%%Koor%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 \psaxes[Ox=0,Dx=2,Oy=0,Dy=2,linewidth=0.1pt]{->}(0,0)(0,0)(4.5,4.5)%Schnittpunkt, x0, y0   x1,y1
 \rput[l](1.7,-0.8){$1.\ Koordinate$} 
 \rput[c](4.8,0){$x$}
 
 \rput[l](0.4,4){$2.\  Koordinate$}
 \rput[c](0,4.8){$y$}
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%Vektor / Gerade%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 \psline[linecolor=red, linewidth=0.1pt](0,0)(3,3)
 \rput[c](3.0,-0.3){$a_1$}  
 \rput[c](-0.3,3){$a_2$}
 
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%Hlfslinien%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 \psline[linecolor=blue, linestyle=dashed, linewidth=0.1pt](3,-0.2)(3,3)
 \psline[linecolor=blue, linestyle=dashed, linewidth=0.1pt](-0.2,3)(3,3)
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%Pfeil%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 \psline{->}(3.5,2.5)(3.1,2.9)

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%Kreuz %%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 \psline[linecolor=green] (2.9,3.1)(3.1,2.9)
 \psline[linecolor=green] (2.9,2.9)(3.1,3.1)
 
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%Beschriftung am Pfeil %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 \rput[l](3.3,2.3){Punkt}
 \rput[l](3.2,1.9){$(a_1, a_2)$}
  \end{pspicture}