FACTORING POLYNOMIALS

A Quick Review

1. Always watch for factors common to all terms. If there is a common factor, then factor it out.

2. Use the number of terms in the expression as an aid in factoring.

A. TWO TERMS: Is the expression a sum or difference of cubes or the difference of two squares?

                                        Difference of two squares:

                                        Difference of two cubes:

                                        Sum of two cubes:

                                        Sum of two squares: WILL NOT FACTOR!

B. THREE TERMS: The expression MAY be a perfect square trinomial.

In a perfect square trinomial, the first and third terms are perfect squares, the middle term is twice the product of the roots of the first and third terms and the second sign is always positive.

A perfect square trinomial factors into a binomial squared.

If an expression with three terms is not a perfect square trinomial then factor it by trial-and-error.

C. FOUR TERMS: Try factoring by grouping. (Remember to pay attention to the middle sign!)

3. Be sure that the expression is factored completely.

4. The factorization may be checked by multiplying it out to be sure that the product is the same as the original expression.

ASSIGNMENT: PAGE 346 – 7, problems 1 – 77, every other odd

problems 81 - 87