Updates:
Summary: solve() could attempt logcombine when looking for solutions
Comment #5 on issue 3149 by smi...@gmail.com: solve() could attempt
logcombine when looking for solutions
http://code.google.com/p/sympy/issues/detail?id=3149
eq
log(f(x)/C1) + log(3*x**2/f(x)**2 + 1)/3 == 0
logcombine(eq,force=True)
log((3*x**2/f(x)**2 + 1)**(1/3)*f(x)/C1) == 0
lc=_
ans=solve(lc,f(x))
Is checksol capable of reducing this solution?
No. But when in doubt, it returns the solution:
[checksol(lc,f(x),a) for a in ans]
[None, None, None]
equals *is* able to confirm the solutions:
lc.subs(f(x),ans[0]).equals(0)
True
lc.subs(f(x),ans[1]).equals(0)
True
lc.subs(f(x),ans[2]).equals(0)
True
So it appears that when dealing with logs a logcombine could be attempted
if hints allow (e.g. if force=True?)
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