rudimental block for second degree inequation



Hallo

I include a rudimental block for solving
inequation with Maxima, solve is only for
equation.
Best regards.

Luigi Marino.

diseq(a,b,c):=block([x1,x2,delta],
delta:b*b-4*a*c, if delta>0 
then x1:(-b-sqrt(delta))/2*a,
x2: (-b+sqrt(delta))/2*a,
if a>0 
then print("S= R - ",[x1,x2]), 
else
print("S = ",[x1,x2]),
if delta=0 and a>0
then print("S= R -(",-b/2*a,")")
else
if a<0 
then print("{}"),
if delta<0 and a>0
then print("S=R")
else
if a<0
then print("S={}") )$

Example:
diseq(1,-7,12);

diseq(1,1,1);

diseq(-1,-1,-1);