-0.5 4.5 setxrange
-1 4 setyrange
50 setxunit
50 setyunit
7.5 setborder
90 setangle_repere
-0.5 4.5 setxrange
-0.5 3.5 setyrange

traceaxes
axesarrow
setTimesItalic
(x) 4.05 0 [1.8 dup] drtext
(y) 0 3 [1.8 dup] ultext


%-0.5 4.5 setxrange
%-1 3 setyrange

/X {0 0} def
/Y {1.5 0.5} def
/Z {0.5 2} def
/A {2.5 1.2} def
/B {4 1.7} def
/C {3 3.2} def

[A B C] polygone
[X Y] (->) ligne
[X Z] (->) ligne
[Z Y] (->) ligne


(O) X [1.5 dup] dltext
(X) Z [1.5 dup] ultext
(Y) Y [1.5 dup] drtext
(A) A [1.5 dup] dltext
(B) B [1.5 dup] drtext
(C) C [1.5 dup] uctext

<latex>
$(-x_1,-x_2)$
</latex>
0.35 2.4 [1.4 dup] drtexlabel


<latex>
$(y_1,y_2)$
</latex>
1.65 0.5 [1.5 dup] drtexlabel

<latex>
$\rm{Abb}.\,4$
</latex>
2.5 -1 [2.0 dup] ultexlabel