Andrey G. Grozin <A.G.Grozin <at> inp.nsk.su> writes:
> limit((sin(x)-x)/x^3,x,0)
> would produce 0
Replace sin(u) with u in products (and quotients) and powers, not in a sum.
sin(x) - x take the first NON ZERO taylor polynomial that is:
sin(x)- x == equivalent == (x - x^3/6 + ...) - x = - x^3 / 6
x - x = 0 is not a NON ZERO taylor polynomial.
Best wishes.
-M