%1er cas de limite : lim(+infini)=l

25 setxunit
7.5 setborder
90 setangle_repere
-1 5 setxrange
-1 5 setyrange
1 1 settkstep
.5 .5 setsubtkstep
2 2 setmkstep
traceaxes
axesarrow
(O) O drtext
setTimesItalic
(x) 4.5 0 drtext
(y) 0 4.5 ultext
/A {0 3} def
/B {5 3} def
[A B] ligne
setSymbol
(D) 4.5 3.5 drtext
setTimesItalic
(l) 0 3 cltext
/m {0 3.4} def
/n {4.5 2.6} def
/p {4.5 3.4} def

/g {setxvar
#rpn#   3+1/x
} def
gsave
   rouge
   .75 setlinewidth
   continu
 0.01 5  {g} Courbe
grestore
setTimesItalic
(C) 3 4 drtext
(f) indice