def F1(x) : 
	retour=pow(x,3)-3*pow(x,2) 
	return retour

pas=0.1 
xdepart=-2 
while (xdepart<4) :
	xfin=xdepart+pas 
	# TRACER_SEGMENT(xdepart,F1(xdepart),xfin,F1(xfin))
	xdepart=xfin