25 setxunit
7.5 setborder
90 setangle_repere
-6 6 setxrange
-5 6 setyrange
1 1 settkstep
1 1 setsubtkstep
2 2 setmkstep
ticks
subticks
marks
traceaxes
axesarrow
unites

/f {setxvar
#rpn#   5*(1-x)/(x^2+x+2)
} def
/g {setxvar
#rpn#   -5/4*(x-1)
} def
gsave
   bleu
   1 setlinewidth
   continu
 5 neg 5  {f} (*-*) Courbe
grestore
gsave
   rouge
   1 setlinewidth
   continu
   {g} courbe
grestore
/f' {  setxvar
0
} def


-1 5 dashpoint
3 5 7 div neg dashpoint
(5) 0 5 [1.5 dup] crtext
<latex> 
$-\frac{5}{7}$
</latex>
0 -5 7 div [1.5 dup] cltexlabel
(T) -3 dup g [1.5 dup] {5 4 div neg 1 atan} urtext
<latex>
$y=\frac{5}{4}(x-1)$
</latex>
2.5 dup g [1.5 dup] {5 4 div neg 1 atan} urtexlabel

noir
1.7 settailletangente          
-1 (f) tangente               
3 (f) tangente