Mathematica factoring

gistfile1.txt

Here is an example input:

In[89]:= AA =  1/(24 \[Eta] \[Tau]C \[Tau]Q) (-12 \[Eta] \[Tau]Q - 12 a^2 GC \[Tau]C \[Tau]Q - 3 \[Zeta] \[Tau]C \[Tau]Q +     5 \[Zeta] \[Xi] \[Tau]C \[Tau]Q +     Sqrt[(48 \[Zeta] \[Eta] (-3 + 5 \[Xi]) \[Tau]C + (12 \[Eta] + (12 a^2 GC + \[Zeta] (3 - 5 \[Xi])) \[Tau]C)^2) \[Tau]Q^2])

This method doesn't work:

In[90]:= Solve[AA == 0, \[Zeta]]

During evaluation of In[90]:= $RecursionLimit::reclim: Recursion depth of 20 exceeded. >>


Putting in quadratic form means the problem can be solved:

In[91]:= BB = (12 \[Eta] + (12 a^2 GC + \[Zeta] (3 - 5 \[Xi])) \[Tau]C)
Solve[BB == 0, \[Zeta]]



Desired solution:
Out[92]= {{\[Zeta] -> (   12 (\[Eta] + a^2 GC \[Tau]C))/((-3 + 5 \[Xi]) \[Tau]C)}}