Source
%% auteur : 

60 setxunit
%9.5 setborder
90 setangle_repere
-5 4 setxrange
-1 4 setyrange
1 1 settkstep
%.5 .5 setsubtkstep
1 1 setmkstep
ticks
subticks
marks
traceaxes
axesarrow
unites

/A{-1.443 -0.53} def
A dashpoint
/g {setxvar
#rpn#   x*2^x
} def       
 -6 6  {g} Courbe
/g'{setxvar
 1 x 2 ln mul add 2 x exp mul}def
2 settailletangente

-1.44 (g) tangente



setTimes
(O) O dltext

<latex>
$-\frac{1}{\ln 2}$
</latex>
-1.44 0.1 [1.7 dup] uctexlabel

<latex>
$-\frac{1}{e\ln 2}$
</latex>
0 -0.5 [1.7 dup] crtexlabel