25 setxunit
7.5 setborder
90 setangle_repere
-3 5 setxrange
-5 13 setyrange
1 1 settkstep
2 2 setmkstep
ticks
marks
traceaxes
unites
/f {setxvar
#rpn#   (x-1)^2 -3
} def
/g {setxvar
#rpn#   x
} def
gsave
   noir
   .75 setlinewidth
   continu
   {f} courbe
grestore
5 settailletangente
2 {f} tangente
3 settailletangente
1 {f} tangente
[1 2] {dup f dashpoint} apply
setTimesItalic
   (O) 0 0 dltext
   (A) 1 -3 dltext
   (B) 2 -2 drtext