-3 4.5 setxrange
-3 3 setyrange
15 setfontsize
30 setxunit
30 setyunit
/B {3 -2} def
/C {3 2} def
/D{-2 2} def
/A {-2 -2} def
[A B C D] points
[A B C D] polygone
[A C] ligne
<latex>
$\displaystyle\sqrt{8}-\sqrt{2}$
</latex>
3.6 0 cctexlabel
<latex>
$\displaystyle\sqrt{8}+2\sqrt{2}$
</latex>
0 -2.5 cctexlabel

setTimesItalic
   (A) A dltext
   (B) B drtext
   (C) C urtext
   (D) D ultext