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Polynomial FunctionsPolynomial Functions
Exploring Polynomial FunctionsExploring Polynomial Functions– ExamplesExamples
Modeling Data with Polynomial Modeling Data with Polynomial FunctionsFunctions– ExamplesExamples
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DegreeDegree Name of Name of DegreeDegree
Number Number of Termsof Terms
Name Name using using
number of number of termsterms
00 ConstantConstant 11 MonomialMonomial
11 LinearLinear 22 BinomialBinomial
22 QuadraticQuadratic 33 TrinomialTrinomial
33 CubicCubic 44 33rdrd degree degree
PolynomialPolynomial
44 QuarticQuartic nn 44thth degree degree Polynomial Polynomial
with n termswith n terms
55 QuinticQuintic 55thth degree degree polynomial polynomial
with n termswith n terms
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Polynomials and Linear Polynomials and Linear FactorsFactors Standard FormStandard Form
– ExampleExample Factored FormFactored Form
– ExamplesExamples Factors and ZerosFactors and Zeros
– ExamplesExamples
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The expression x-a is a linear factor of a polynomial if and only if thevalue a is a zero of the related polynomial function.
Factor TheoremFactor Theorem
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Factors and ZerosFactors and Zeros
-3-3 -2-2 -1-1 00 11 22 33
(x – (-3)) or (x + 3)(x – (-3)) or (x + 3) (x – (-2)) or (x + 2)(x – (-2)) or (x + 2) (x – (-1)) or (x + 1)(x – (-1)) or (x + 1) (x – 0) or x(x – 0) or x (x – 1)(x – 1) (x – 2)(x – 2) (x – 3)(x – 3)
ZEROS FACTORS
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Dividing PolynomialsDividing Polynomials
Long DivisionLong Division Synthetic DivisionSynthetic Division
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Long DivisionLong Division
The purpose of this type of division The purpose of this type of division is to use one factor to find is to use one factor to find another.another.
)4 40
Just as 4 finds the 10
)x - 1 x3 + 6x2 -6x - 1
The (x-1) finds the (x2 + 7x + 1)
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Synthetic DivisionSynthetic Division
When dividing by x – a, use When dividing by x – a, use synthetic division.synthetic division.
The Remainder TheoremThe Remainder Theorem
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The Remainder The Remainder TheoremTheorem When using Synthetic Division, When using Synthetic Division,
the remainder is the value of f(a).the remainder is the value of f(a). This method is as good as This method is as good as
“PLUGGING IN”, but may be “PLUGGING IN”, but may be faster.faster.
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Solving Polynomial Solving Polynomial EquationsEquations Solving by GraphingSolving by Graphing Solving by FactoringSolving by Factoring
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Solving by GraphingSolving by Graphing
Set equation equal to 0, then Set equation equal to 0, then substitute y for 0. Look at the x-substitute y for 0. Look at the x-intercepts. (Zeros)intercepts. (Zeros)
Let the left side be yLet the left side be y11and let the and let the right side be yright side be y22. (Very much like . (Very much like solving a system of equations by solving a system of equations by graphing). Look at the points of graphing). Look at the points of intersection.intersection.
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Solving by FactoringSolving by Factoring
Sum of two cubesSum of two cubes
(a(a33 + b + b33) = (a + b)(a) = (a + b)(a22 – ab + b – ab + b22))
Difference of two cubesDifference of two cubes
(a(a33 – b – b33) = (a – b)(a) = (a – b)(a22 + ab + b + ab + b22))
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More on FactoringMore on Factoring
If a polynomial can be factored If a polynomial can be factored into linear or quadratic factors, into linear or quadratic factors, then it can be solved using then it can be solved using techniques learned from earlier techniques learned from earlier chapters.chapters.
Solving a polynomial of degrees Solving a polynomial of degrees higher than 2 can be achieved by higher than 2 can be achieved by factoring.factoring.
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Theorems about RootsTheorems about Roots
Rational Root TheoremRational Root Theorem Irrational Root TheoremIrrational Root Theorem Imaginary Root TheoremImaginary Root Theorem
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Rational Root TheoremRational Root Theorem
What are Rational Roots?What are Rational Roots? P’s and Q’s ………. ;)P’s and Q’s ………. ;) Using the calculator to speed up Using the calculator to speed up
the process.the process.
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……And the Rational And the Rational Roots are…..Roots are…..
q
p P includes all of the factors of the constant.
Q includes all of the factorsof the leading coefficient.
f(x) = x3 – 13x - 12
p = 12q = 1
The possible rational roots are:
1,2,3,4,6,12
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Test the Possible Test the Possible Roots…Roots…
In this case all roots are real and rational, but you need onlyto find one rational root. This will become clear later.
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Since -1, -3, and 4 are the Roots,
(x + 1), (x + 3), and (x – 4)
are the factors.
Multiply to show that
(x+1)(x+3)(x-4) = x3 – 13x – 12
(x+1)(x2 – x – 12)
x3 – x2 – 12x +x2 – x – 12
x3 – 13x – 12
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Irrational Root Irrational Root TheoremTheorem
If is a root, then is too.
ba ba
These are called CONJUGATES.
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Imaginary Root Imaginary Root TheoremTheorem
These are called CONJUGATES.
If is a root, then is too.
bia bia
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The Fundamental The Fundamental Theorem of AlgebraTheorem of Algebra If P(x) is a polynomial of degree If P(x) is a polynomial of degree
with complex coefficients, with complex coefficients, then P(x) = 0 has at least one then P(x) = 0 has at least one complex root. complex root.
A polynomial equation with degree A polynomial equation with degree n n will have exactly will have exactly nn roots; the roots; the related polynomial function will related polynomial function will have exactly have exactly nn zeros. zeros.
1n
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The Binomial TheoremThe Binomial Theorem
Binomial Expansion and Pascal’s Binomial Expansion and Pascal’s TriangleTriangle
The Binomial TheoremThe Binomial Theorem