12 setfontsize
-2 10 setxrange
-1 5 setyrange

25 setxunit
[1 1 .5 .5 .1 .1] {orange} Quadrillage
.7 setlinewidth

/f {
   argcosh
} def

/unites {} def
tracerepere
marks

<tex>
$$
   y = {\rm Arg\ ch}\,  x
$$
</tex>

/dx_boxit 3 def
/dy_boxit 3 def
/linearc .05 def
/fillstyle {jaune fill} def
boxit
3 4 [2 dup] cctexlabel
   
1.5 setlinewidth
gsave
   bleu
   1 xmax {f} Courbe
grestore

setTimesItalic
   (O) O drtext