%% auteur : 

-3 3 setxrange
-3 3 setyrange
60 setxunit
%tracerepere
/O{0 0} def
/cerc{O 2} def
/N{30 cerc cpoint} def
/A{220 cerc cpoint} def
/B{320 cerc cpoint} def
/M{100 cerc cpoint} def
%/M{Z N 36 rotatepoint} def
cerc cercle
[N A] ligne
[N B] ligne
[M A] ligne
[M B] ligne
A M B .5 tripointarc
N A M .5 tripointarc
O point
setTimesItalic
(A) A [2 2] dltext
(B) B [2 2] drtext
(O) O [2 2] ultext
(M) M [2 2] utext
(N) N [2 2] urtext
(I) N A M B interdroite [2 2] dtext
setTimes
   (50°) -85 M 0.7  cpoint [2 2] cctext
(40°) 45 A 0.8  cpoint [2 2] cctext