i'm making program that will solve ax^3+bx^2+cx+d=0 :
dim a,b,c,d,x
a=inputbox("enter a")
b
c
d
'b,c,d is coded like a'
for x=-1000 to 1000 step 0.1
s=ax^3+bx^2+cx+d
if s=0 then msgbox"x is ok:&x"
next
x
. i use " for .... step " but when i run program it's not so .ex:0.1 is 0.09999999.please help me