Multiplying Polynomials

1
Multiplying Polynomials

• Be able to use different methods to multiply two
  polynomials.

2
Multiplying Polynomials

• To multiply polynomials together each term of the
  first polynomial must be multiplied by each term
  of the second polynomial.
• There are several methods for multiplying
  polynomials.
• The three methods we will be using are the box
  method, using the memory device FOIL, and using
  the distributive property.

3
The Box Method

• The simplest method for multiplying polynomials
  is to use a box or a chart to fill in. Here is
  an example

4
How does FOIL work?

• Look at the example below to show FOIL at work
• F multiply the first term in each binomial
• O multiply the two outside terms together
• I multiply the two inside terms together
• L multiply the last term in each binomial
• (x 6)(2x 3)
• 
  
• 2x2 3x 12x 18 2x2 15x
  18

6
2x
x
2x
3
6
3
x
5
The Distributive Method

• The third method is to use the distributive
  property to multiply each term of the first
  polynomial by each term of the second polynomial.
  You must use this method or the box method if
  you are multiplying polynomials that are not
  binomials.

6
Lets Practice
3. (5 x)(5 x) 25 5x 5x x2
25 x2 4. (y 2)2 (y 2)(y
2) y2 2y 2y 4 y2
4y 4

• 1. (y 5)(y 1)
• y2 y 5y 5
• y2 6y 5
• 2. (3xy 4)(4xy 5)
• 12x2y2 15xy 16xy 20
• 12x2y2 xy 20