Source
%% auteur : Peric
28.54 setxunit
28.54 setyunit
/quadrillagegray 0.6 def
1 setquadrillagexstep
1 setquadrillageystep
quadrillage

/xmarkstyle {[2 dup] dltext} def
/ymarkstyle {[2 dup] ultext} def
-10 10 setxrange
-5 5 setyrange
%1 1 settkstep
%1 1 setmkstep
%ticks
%marks
%0 xmark
%traceaxes
%axesarrow
%unites


/t {2}def
/ahlength {10} def
2 setlinewidth 
1 setlinejoin

/A {-8 2} def
/B {5 1} def
/u {3 1 } def
/v {2 -4} def
/E {A u v addv translatepoint} def
/F {B u -3 mulv translatepoint} def
/C {F v 0.5 mulv translatepoint} def

[A B] {plus3} papply
[-8 2 -5 3] (->) ligne 
[-8 2 -6 -2] (->) ligne 
[A E] (->) ligne
[B C] (->) ligne

(A) A [t dup] ultext
(B) B [t dup] ultext
(C) C [t dup] drtext

<latex>
$\overrightarrow{u}$
</latex>
-8 2 -5 3 milieu [t dup] uctexlabel
<latex>
$\overrightarrow{v}$
</latex>
-8 2 -6 -2 milieu [t dup] dltexlabel
<latex>
$\overrightarrow{v}$
</latex>
A u translatepoint E milieu [t dup] urtexlabel
<latex>
$\overrightarrow{u}+\overrightarrow{v}$
</latex>
A E milieu [t dup]{-3 5 atan} uctexlabel
<latex>
$-3\overrightarrow{u}$
</latex>
B F milieu [t dup] ultexlabel
<latex>
$\frac12\overrightarrow{u}$
</latex>
F C milieu [t dup] dltexlabel
<latex>
$-3\overrightarrow{u}+\frac12\overrightarrow{u}$
</latex>
B C milieu [t dup] drtexlabel

gsave
1 setlinewidth
[A u translatepoint E ] (->) ligne
[B F] (->) ligne
[F C] (->) ligne

grestore