Pour recommencer, \reload{<img src="gifs/doc/etoile.gif" alt="rechargez" width="20" height="20">}
\def{real a =randint(1,2)}
\def{text liste= (x^2-\a^2)^(1/2), (x-\a)^(1/2)}
\def{function  f= randitem(\liste)}
\def{integer c=randint(1..2)}
\def{real  b= \a+ \c}
\def{function h= \c*(1-s)^2}
\def{text P=\a, evalue(\f,x=\a)}
\def{text P0=\a, 0}
\def{text Q0=0, evalue(\f, x=\a)}
\def{text legende= 0, -1}
\def{text P1= \a+(\h),0}
\def{text Q=\a+(\h), evalue(\f, x=\a+(\h))}
\def{text Q1=0, evalue(\f, x=\a+(\h))}
\def{real mx= min(\a-1,-1)}
\def{real Mx= \a+\c+1}
\def{real my= -1}
\def{real My =2}
\def{function pente=(item(2,\Q)-item(2,\P))*(x-(\a))/(\h)+item(2,\P)}
\def{real larg= \Mx-\mx}
\def{real haut= \My-\my}
\def{integer prop1= 100}
\def{integer prop2= 100*\haut/\larg}


<center> \draw{300,300}{
animate 24, 0.5, 5
animstep 12
xrange \mx,\Mx
yrange \my-1,\My
arrow 0,0, 0,\My,10,black
arrow 0,0, \Mx,0 ,10,black
vline 0,0, black
hline 0,0, black
linewidth 3
line \P,\Q, red
linewidth 3
vline  \a,0, yellow
plot red, \pente
linewidth 2
plot  black, \f
plot  black, -\f
linewidth 1
dline \P, \P0, green
dline \P, \Q0, green
dline \Q, \P1, red
dline \Q, \Q1 , red
text black, \legende, normal,f(x)=\f, a=\a
text red, \Q, normal,(a+h,f(a+h))
}
</center>




