-3 3 setxrange
-3 3 setyrange

/A {2 2 sqrt} def
/B {2 sqrt neg 2} def
/C {2 sqrt neg -2} def
/I {0 2} def
/J {2 3 pi mul 4 div polcar} def
/K {J -1 0 mulc} def

quadrillage
tracerepere
marks

[A B C I J K] points

[I J K] polygone

J I K angledroit

/r 6 sqrt def
O r cercle
O 2 cercle

gsave
newpath
   0 r smoveto
   O r cercle_
   0 2 smoveto
   O 2 cercle_
closepath
eoclip
hachure
grestore

setTimesItalic
   (A) A urtext
   (B) B ultext
   (C) C dltext
   (I) I (3 1) drtext
   (J) J dctext
   (K) K cltext
   (O) O dltext