4.2 Division.notebook
September 30, 2013
Section 4.2: Properties of Division In this chapter will be trying to “factor” polynomials in order to find their zeros.
… Polynomial
… Factors
… Zeros
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4.2 Division.notebook
September 30, 2013
Since the polynomial has a degree of 3, there will be three factors and three zeros. By the end of the chapter we will be able to find these 3, but for now, all we will be asked to do is state if a something is a factor or not.
3 Different Methods:
• Long Division
• Synthetic Division
• Substitution First…Let’s review the process of long division.
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4.2 Division.notebook
September 30, 2013
Method #1:
Long Division: Method #2:
Synthetic Division: Method #3:
Substitution: 3
4.2 Division.notebook
September 30, 2013
Method #1:
Long Division: Method #2:
Synthetic Division: 4
4.2 Division.notebook
September 30, 2013
The long division problems for homework are somewhat tricky…let’s try a few more….
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4.2 Division.notebook
September 30, 2013
Now work backwards….
Given the zeros ­ find the polynomial. Ex: Find a polynomial of degree 3 that has zeros 2, ­1, and 3.
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4.2 Division.notebook
September 30, 2013
Homework Starter:
Pg. 266: • Parabolic Arch: An arch has the shape of the parabola y = 4 ­ x2. A rectangle is fit under the arch by selecting a point (x, y) on the parabola.
a. Express the area A of the rectangle in terms of x.
b. If x=1, the rectangle has base 2 and height 3. Find the base of a second rectangle that has the same area.
Answer:
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4.2 Division.notebook
September 30, 2013
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