Hello BGYour only hope would be to find the factors of the numerator and denominator - and then 'cancel' the common factor, which turns out to be ; i.e.

The only way I can suggest you might have done this is to use a 'trial and error' process on each of the quartic expressions. Given that, for example, cannot be broken down in many ways -

- ; and

- this shouldn't have taken too long.

But I must admit: I cheated and worked back from the answer you gave me using algebraic long division.

Does that help to shed some light?

Grandad