If a polynomial function f(x)has root -2 + square root 8 and 9 what must be a factor of f(x)

Step-by-step explanation:

Given that f(x) is a polynomial function.

This implies that f(x) has x terms of positive integral degrees and also rational coefficients only.

Since an irrational root is given a root of f(x), we find that its conjugate also should be a root of f(x)

i.e. If is a root, then is also a root.

(Because this only when multiplied will make coefficients rational)

So the factors of f(x) should be atleast

There can be other factors also but this is compulsory