POLYNOMIALS LESSON 3.3 FACTORING
POLYNOMIALS A math equation consisting of one to many terms. Examples: 6, x, 6x, -1/2xy, 2y + x, x 2 – 5x - 9 Polynomials cannot have a variable as a denominator nor negative exponents.
Are the following polynomials? 7/a ¼ xy – 10 3pq 1/2 √7 x 4 – x
Polynomials with one term are called monomials 5x 3, 8, x 2, etc two terms are called binomials 3x – 1, 2x 2 + 8, etc three terms are called trinomials 2x 2 – 4x + 9
Variables – a letter that represents one or more numbers 4y = y is the variable Coefficient – number in front of a variable 4y = coefficient is 4
DEGREES OF A POLYNOMIAL The degree of a polynomial is the degree of the term with the highest exponent. Constant term: term without a variable.
2x – 1 = degree of 1Constant term of -1 These are called a linear. 2x = degree of 2 Constant term of 8 These are called quadratic. 2x 3 – 5 = degree of 3 Constant term of -5 These are called cubic.
EXAMPLE 1 State the degree, coefficient’s and constant term of the polynomial. 5x 3 + x 2 – 7x + 9
EXAMPLE 2 State the degree, coefficient and constant term of the polynomial. 6a – 4a 2 - 3
ADDING AND SUBTRACTING POLYNOMIALS Find like terms and combine them in order to simplify polynomials. 4x – 2x – 6x – x
TRY THE FOLLOWING a 2 b – ab 2 + 4a 3 b – 7ab 2 + 5a 2 b (3a – 4b + c) + (3b – 5c – 3a)
BE CAREFUL WITH SUBTRACTION (4x 2 – 9x + 6) – (2x 2 – 3x – 1)
Work on Handout
FACTORING LINEAR POLYNOMIALS Just as natural numbers can be factored so can polynomials. Find the GCF in each term and then factor.
FACTORING EXAMPLES 4m + 12 GCF = 4 = 4 (m + 3)
6 – 15a GCF = 3 = 3 (2 – 5a)
TRY THE FOLLOWING 6n + 9 = 6c + 4c 2 = 3g + 6 = 8d + 12d 2 =
FACTORING TRINOMIALS ax 2 + bx + c 5 – 10z – 5z 2 Find the GCF of all three terms. In this example the GCF is 5. Factor out a 5 from each and write as a product. 5 ( 1 – 2z – z 2 )
EXAMPLES 18a 2 – 12a x – 45x 2
FACTORING WITH MORE THAN ONE VARIABLE Find all GCF’s, numbers and letters. -12 x 3 y – 20xy 2 – 16x 2 y 2 GCF for numbers = 4 GCF for letters = 1x and 1y 4xy (-3x 2 – 5y – 4xy)
5ab a 2 b 3 – 15a 2 b 4
- 20c 4 d - 30c 3 d 2 – 25cd
Work on textbook questions # 6, 7, 8, 9, 10, 14.