Consider the functions:
has a single real (i.e., containing no imaginary part) solution.
Let's call that solution .
Find an exact value (no decimal approximation) for h(S) .
Now change the in f to and re-execute the solve command you used. Once again, there are multiple solutions but only one is real (i.e., has no imaginary part). Can you read the solution? If not, get someone to help decipher it for you, so that you will know how to deal with such solutions in the future.