Answer:x^3-3x^2-18x-14
Explanation:
It needs to be a polynomial function so there can't be any square roots in the function.
So to get rid of the square root in 2+3√2, we need a 2-3√2.
So the function is (x+1)(x-[2+3√2]}(x-[2-3√2])=0
which is (x+1)(x-2-3√2)(x-2+3√2) which is (x+1)([x-2]^2-18)
which is (x+1)(x^2-4x+4-18)=(x+1)(x^2-4x-14) which is x^3-3x^2-18x-14