The polynomial is .

The binomial is a factor of polynomial.

Here is a zero of the realted polynomial function.

Use synthetic division to find remaining factor of the polynomial.

Since the remainder is zero, is a factor of polynomial.

The polynomial can be factored as .

The polynomial is the depressed polynomial.

                    (Factor the trinomial)

Hence, .

Check:

Multiply the factors and check whether it is intial polynomial or not.

                                         (Factors)

                                  (Group the factors)

    (Foil method)

                                     (Multiply)

                    (Distributive property: )

                     (Multiply)

                                       (Simplify)

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