Source
25 setxunit
7.5 setborder
90 setangle_repere
-1 10 setxrange
-1 10 setyrange
1 1 settkstep
.5 .5 setsubtkstep
2 2 setmkstep
traceaxes
unites
/f {setxvar
#rpn#   x
} def
/g {setxvar
#rpn#   1/x+x
} def
gsave
   bleu
   .75 setlinewidth
   continu
 0 xmax  {f} Courbe
grestore
gsave
   rouge
   .75 setlinewidth
   continu
 .01 xmax  {g} Courbe
grestore

<tex>
$\vec \imath $
</tex>
.4 -.1 [1.5 dup] dctexlabel

<tex>
$\vec \jmath $ 
</tex>
-.1 .2 [1.5 dup] ultexlabel

rouge

<tex>
$y=t+{1\over t}$
</tex>
0.3 8 [1.5 1.5] urtexlabel

bleu

<tex>
$y=t$
</tex>
6 6 [1.5 1.5] drtexlabel

noir
setTimesItalic
(O) O [1.5 1.5] dltext

/A {3 3} def
/B {3 3.33} def

/C {3 0} def

pointilles
[B C] ligne

(N) A [1.5 1.5] drtext
(M) B [1.5 1.5] ultext