%% auteur : GM

100 setxyrapport
36 setxunit
7.5 setborder
90 setangle_repere
-1 11 setxrange
-100 600 setyrange


traceOx
axeOxarrow
/f {setxvar
#rpn#   x*(22-2*x)*(18-2*x)
} def
/fillstyle {0.9 0.9 0.9 setrgbcolor fill} def 0 9 {f} Fillcourbe 

0 9 {f} Fillcourbe 

gsave
  
   .75 setlinewidth
   continu




  0  9 {f} Courbe
grestore



/A{0 0} def
/B{9 0} def
2 setlinewidth
[A B] ligne

<tex>
  $a$
</tex>
O [2.5 2.5]dctexlabel

<tex>
  $b$
</tex>
9 0 [2.5 2.5]dctexlabel

<tex>
  $I$
</tex>
4.5 0 [2.5 2.5]dctexlabel



<latex>
  $\mathcal{C}_f$
</latex>
0 180 [2.5 2.5]dctexlabel


<latex>
  $1\; ua$
</latex>
4  200 [4 4]uctexlabel