I was going to simplify an equation with three variables (s, a, b) using Mathematica as follows:
In[3]:= f[s_] := ((1/4)*(s + s^2 + s^3 + s^4)*[a*(s^3 - s) +
b*(s^3 - s^2)])/(s^3 - (1/4)*(s + s^2 + s^3 + s^4))
In[4]:= Simplify[f[s_]]
Out[4]:= s_ (1 + s_ + s_^2)
As you can see, in the simplified version does not have 'a' and 'b'. I am sure that they should not be removed during simplification process. I am wondering what I am missing...
Thank you in advance!!!
Square brackets have very precise meaning in Mathematica and can't be used in place of parens. Likewise underscores can only be used in very specific ways.
Try this
f[s_] := (1/4*(s+s^2+s^3+s^4)*(a*(s^3-s)+b*(s^3-s^2)))/(s^3-1/4*(s+s^2+s^3+s^4));
Simplify[f[s]]
which gives you this
-((s*(a + a*s + b*s)*(1 + s + s^2 + s^3))/(-1 - 2*s + s^2))