%% auteur : gh

150 setxunit
-0.5 1.5 setxrange
-0.1 1.4 setyrange

traceaxes
axesarrow
1.7 setlinewidth

0.3 pi 3 div settrange

/O {0 0} def
16 setfontsize
setTimesItalic
   (O) O dltext


/X {4 mul Cos neg} def
/Y {3 mul Sin} def

/X' {4 mul Sin} def
/Y' {3 mul Cos} def

{X} {Y} courbeparam


/t 0.6 def
/Mt {t X t Y} def
/vt {t X' t Y'} def

rouge
Mt point
Mt vt vect
<tex>
$$ \vec{f}'(t_0) $$
</tex>
Mt Mt vt addv milieu [1.5 1.5] urtexlabel
bleu
O Mt (->) line
<tex>
$$ \vec{f}(t_0) $$
</tex>
O Mt milieu [1.5 1.5] ultexlabel
<tex>
$$ M(t_0) $$
</tex>
Mt [1.5 1.5] uctexlabel