Source
-2.5 5 setxrange
-0.8 3 setyrange

1 setxyrapport
60 setxunit
7.5 setborder
90 setangle_repere
-0.7 4 setxrange
-0.7 3 setyrange
1 1 settkstep
.5 .5 setsubtkstep
2 2 setmkstep
%ticks
%subticks
%marks
traceaxes
axesarrow

%unites
/f {setxvar
#rpn#   (7/10*x^2-41/20*x+37/20)
} def

/g {setxvar
#rpn#   (-1/4*x+17/8)
} def


/M {0.5 0} def
/P {0.5 1} def
/N {2.5 0} def
/Q {2.5 1.1} def
/E {1.75 0} def
/F {1.75 0.40625} def
/P1 {0.5 2} def
/Q1 {2.5 1.5} def
/F1 {1.75 1.6875} def
/Y1 {0 2} def
/Y2 {0 1.5} def
/Y {0 1.6875} def


setTimesItalic
(O) O [1.8 dup] drtext
(x) 3.7 0 [1.8 dup] drtext
(y) 0 2.7 [1.8 dup] ultext
(y) 0 1.6875 [1.8 dup] cltext
(P') F F1 P Q interdroite [1.5 dup] ultext

<latex>
$P_1$
</latex>
P1 [1.5 dup] uctexlabel

<latex>
$P_2$
</latex>
Q1 [1.5 dup] uctexlabel

<latex>
$P$
</latex>
F1 [1.5 dup] uctexlabel

<latex>
$P_1'$
</latex>
P [1.5 dup] dltexlabel

<latex>
$P''$
</latex>
F [1.5 dup] ultexlabel

<latex>
$P_2'$
</latex>
Q [1.5 dup] crtexlabel

gsave
pointilles
[M P1] ligne
[N Q1] ligne
[E F1] ligne
[F1 Y] ligne
[P1 Y1] ligne
[Q1 Y2] ligne
grestore

[P F Q P1 F1 Q1 F F1 P Q interdroite ] points
[P Q] ligne
[P1 Q1] ligne
gsave
   noir
   1 setlinewidth
   continu
-0.2  3 {f} Courbe
grestore



<tex>
$x_1$
</tex>
M [1.8 dup] dctexlabel

<tex>
$x_2$
</tex>
N [1.8 dup] dctexlabel

<tex>
  $x$
</tex>
E [1.8 dup] dctexlabel

<tex>
$y_1$
</tex>
Y1 [1.8 dup] cltexlabel

<tex>
$y_2$
</tex>
Y2 [1.8 dup] cltexlabel

<latex>
$f$
</latex>
%boxit
3.0 2.0 [1.8 dup] dctexlabel

<latex>
$\rm{Abb}.\,10$
</latex>
-1.3 1.2 [2.0 dup] ultexlabel