Source
%%auteur : Florent Braisaz

1 setxyrapport
25 setxunit
7.5 setborder
90 setangle_repere
-6.8 15.8 setxrange
-3.8 15.8 setyrange
1 1 settkstep
.5 .5 setsubtkstep
2 2 setmkstep
ticks
traceaxes
unites

/z0 {1 3} def
/z1 {3 5} def
/z2 {5 7} def
/z3 {7 10} def
/z4 {9 7} def
/z5 {11 4} def
/z6 {12 2} def
/z7 {13 3} def
/z8 {14 5} def
%%/z9 {15 0} def

gsave

bleu
0.75 setlinewidth
[z0 .. z1 .. z2 .. z3  .. z4 .. z5 .. z6 .. z7 .. z8] draw

grestore

gsave
noir
setTimesItalic

#latex#${\overrightarrow{i}}$
1 0 [2 2] dctexlabel
#latex#${\overrightarrow{j}}$
0 1 [2 2] cltexlabel

(O) 0 0 [2 2] dltext

#latex#${\mathcal{C}_f}$
13 2 [2 2]  crtexlabel

grestore

z3 dashpoint

#latex#${A\big(a;f(a)\big)}$
z3 [2 2] urtexlabel

#latex#${a}$
7 0 [2 2] dctexlabel

#latex#${M=f(a)}$
0 10 [2 2] cltexlabel

<latex>
\begin{center}La fonction ${f}$\\ admet $M$ pour \\ maximum...\end{center}
</latex>
boxit
-0.5 11 [2 2] ultexlabel

<latex>
\begin{center}... Et ce maximum \\est atteint en ${a}$.\end{center}
</latex>
boxit
8 -0.5 [2 2] drtexlabel