SECTION 5.4
Multiplying Polynomials
MULTIPLYING POLYNOMIALS
We just extend the distributive property.
First
terms
Last terms
Inner
terms
Outer
terms
In the case of two binomials, its usually called
the FOIL method.
EXAMPLE 1
Find each product.
4
a. −3𝑎 4 + 𝑎
b.
(2𝑚 + 6)(5𝑚 − 3)
EXAMPLE 2
2𝑦 5 (𝑦 − 8)(𝑦 + 2)
EXAMPLE 3
(4𝑧 + 2)(𝑧 2 − 3𝑧 − 5)
DIFFERENCE OF TWO SQUARES PATTERN
What
happens below?
𝑥+𝑦 𝑥−𝑦 =
EXAMPLE 4
a.
b.
𝑦+2 𝑦−2
(5𝑟 + 4𝑠)(5𝑟 − 4𝑠)
DIFFERENCE OF TWO SQUARES PATTERN
What
happens below?
(𝑥 + 𝑦)2 =
EXAMPLE 5
(5𝑟 − 7𝑠)2
SECTION 5.5
Dividing Polynomials
THINK BACK TO FRACTIONS . . .
What happens below?
1 4
+ =
6 6
EXAMPLE 1
27𝑚4 −18𝑚3 +9𝑚
a.
9
12𝑎𝑏2 𝑐 + 10𝑎2 𝑏𝑐 +18𝑎𝑏𝑐 2
b.
6𝑎2 𝑏𝑐
THINK BACK TO LONG DIVISION . . .
24 33482
EXAMPLE 2
(𝑥2 + 14𝑥 + 45) ÷ (𝑥 + 9)
EXAMPLE 3
8𝑚3 − 18𝑚2 + 37𝑚 − 13
2𝑚2 − 3𝑚 + 6
WHAT HAPPENS IF WE HAVE MISSING TERMS?
What
happens with 1001 ÷ 5?
Write
the polynomial in standard form.
If
any power is missing, use a zero to
hold the place of that term.
EXAMPLE 4
2𝑥4 + 3𝑥3 – 7𝑥 − 10
𝑥2 – 2𝑥
EXAMPLE 5
9𝑘4 + 12𝑘3 – 4𝑘 − 1
3𝑘2 – 1
QUESTIONS???
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