-1 1 setxrange -1 1 setyrange /X {-0.7 0} def /Y {0.7 0} def /M {X Y milieu} def /c {X Y diamcercle} def 75 c cpoint /C defpoint 225 c cpoint /A defpoint 315 c cpoint /B defpoint [A B C] polygone [M A] ligne B A C 0.12 (-) tripointarc C B A 0.12 (-) tripointarc A C B 0.12 (-) tripointarc [A B C M] points 0 3600 c Cercle (A) A [1.5 dup] dltext (B) B [1.5 dup] drtext (C) C [1.5 dup] uctext (M) M [1.5 dup] uctext $a$ 0.5 0 [1.6 dup] ultexlabel $c$ 0.1 -0.62 [1.6 dup] ultexlabel $b$ -0.15 0 [1.6 dup] ultexlabel $r$ -0.1 -0.2 [1.6 dup] ultexlabel $\gamma$ 0.25 0.4 [1.6 dup] ultexlabel $\alpha$ -0.4 -0.48 [1.6 dup] urtexlabel $\beta$ 0.28 -0.49 [1.6 dup] urtexlabel