I have some functionals that have lots of parameters, but all are volume integrals (not really important...)
It's a variational function I'm minimizing and I'm only keeping the real solution (because it's my variational wavefunction and I demand only a real solution :) ).
Solve[D[Subscript[E, HO][\[CapitalPsi]] + Subscript[E, Int][\[CapitalPsi]], b] == 0, b]
Solve for a parameter b. I get 5 roots, which is correct (fifth degree polynomial). Even when I add
, Reals (no change, still five solutions, of which 4 complex) and try
Reduce (some evil error message and none of the five answers). I even tried:
Simplify[Solve[D[Subscript[E, HO][\[CapitalPsi]] + Subscript[E, Int][\[CapitalPsi]], b] == 0, b], Element[b, Reals]]
Which apparently doesn't seem to work. The four complex solutions are of the form (-1)^(1/5) times a bunch of numbers/parameters. What can I do to filter out the rest (or only keep the first solution)?