The polynomial is .

The binomial is a factor of polynomial.

Here is a zero of the related 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)

.