second verion maxima and minima points of a function

Hi 
My block (simplest  function how said Mr. Fateman)
have the purpose to test really capability of CAS Maxima.
Solve is very hard, Maple and other CAS  have any limititation.
It is a new version that found also inflection point only
as a zero of second derivative.  

load(descriptive);

stud_funz(f):=block([p,fs,fp],
p:solve(diff(f,x,1),x),
fs:diff(f,x,2),
fp:ev(fs,x:p),
for i:1 thru length(float(p)) do 
if floor(rhs(fp[i]))#0 and rhs(fp[i])>0 then print("minimo",[p[i],rhs(ev(f,x:p[i]))])
else if floor(rhs(fp[i]))#0 then print("massimo",[p[i],rhs(ev(f,x:p[i]))])
else print("flesso",[p[i],rhs(ev(f,x:p[i]))]))$

Example:
f:x^3/(1-x^2);

minimo[x=-sqrt(3),(3*sqrt(3))/2]
massimo[x=sqrt(3),-(3*sqrt(3))/2]
flesso[x=0,0]

Best regards.

Luigi Marino