200 setxyrapport
50 setxunit
7.5 setborder
90 setangle_repere
-2 6 setxrange
-50 2000 setyrange
/quadrillagegray 0.4 def
1 setquadrillagexstep
100 setquadrillageystep
quadrillage
1 50 settkstep
.5 50 setsubtkstep
2 100 setmkstep
ticks
subticks
marks
traceaxes
axesarrow
unites
/f {setxvar
#rpn#   50*x^2
} def
/g {setxvar
#rpn#   100*x^2
} def
/h {setxvar
#rpn#   25*x^2
} def
gsave
   bleu
   .75 setlinewidth
   continu
  0  xmax {f} Courbe
grestore
gsave
   rouge
   .75 setlinewidth
   mixte
  0  xmax {g} Courbe
grestore
gsave
   vert
   .75 setlinewidth
   mixte
  0  xmax {h} Courbe
grestore
(O) O drtext
/A {4 1600} def
/B {4 800} def
/C {4 400} def
[A B C] points
(A) A drtext (B) B drtext (C) C drtext
/P {2 1600} def
P A(->) line
P B(->) line
P C(->) line
arrow
(C) 4 1900 urtext
(g) indice
(C) 5.5 1700 urtext
(f) indice
(C) 5.5 900 urtext
(h) indice
setTimesBold
boxit
(tracé de f(v), g(v), h(v)) 1 1900  urtext
setTimes
boxit
(g(v)=2f(v) et h(v)=0.5 f(v)) 1 1600 urtext