7.4-7.6.

Slides:



Advertisements
Similar presentations
Rational Root Theorem.
Advertisements

Creating Polynomials Given the Zeros.. What do we already know about polynomial functions? They are either ODD functions They are either EVEN functions.
6.5 & 6.6 Theorems About Roots and the Fundamental Theorem of Algebra
2.4 – Zeros of Polynomial Functions
Unit 3 Practice Test Review. 1a) List all possible rational zeros of this polynomial: 5x 4 – 31x x 2 – 31x + 6 p  1, 2, 3, 6 q  1, 5 p  1, 2,
Section 3.4 Zeros of Polynomial Functions. The Rational Zero Theorem.
Lesson 2.5 The Fundamental Theorem of Algebra. For f(x) where n > 0, there is at least one zero in the complex number system Complex → real and imaginary.
6.7 – Using the Fundamental Theorem of Algebra
Solving Quadratic Equations (finding roots) Example f(x) = x By Graphing Identifying Solutions Solutions are -2 and 2.
Zeros of Polynomials PolynomialType of Coefficient 5x 3 + 3x 2 + (2 + 4i) + icomplex 5x 3 + 3x 2 + √2x – πreal 5x 3 + 3x 2 + ½ x – ⅜rational 5x 3 + 3x.
4-5, 4-6 Factor and Remainder Theorems r is an x intercept of the graph of the function If r is a real number that is a zero of a function then x = r.
GUIDED PRACTICE for Example How many solutions does the equation
5.6 Notes: Find Rational Zeros. Rational Zeros: Where the graph crosses the x-axis at a rational number Rational Zero Theorem: To find the possible rational.
Roots & Zeros of Polynomials III
7.5.1 Zeros of Polynomial Functions
Using Technology to Approximate Roots of Polynomial Equations.
Finding Real Roots of Polynomial Equations
6.6 The Fundamental Theorem of Algebra
Quick Crisp Review Zeros of a polynomial function are where the x-intercepts or solutions when you set the equation equal to zero. Synthetic and long division.
OUTLINE  Homework (and homework questions)  Ask any review questions you want  Review long division, solve by factoring and graphing calculators  BREAK.
6-5 Theorems About Roots of Polynomial Equations
5.5 Theorems about Roots of Polynomial Equations P
6.9 Rational Zero Theorem Parts of a polynomial function f(x) oFactors of the leading coefficient = q oFactors of the constant = p oPossible rational roots.
 Evaluate a polynomial  Direct Substitution  Synthetic Substitution  Polynomial Division  Long Division  Synthetic Division  Remainder Theorem 
7.6 Rational Zero Theorem Algebra II w/ trig. RATIONAL ZERO THEOREM: If a polynomial has integer coefficients, then the possible rational zeros must be.
Ch 2.5: The Fundamental Theorem of Algebra
Lesson 2.5, page 312 Zeros of Polynomial Functions Objective: To find a polynomial with specified zeros, rational zeros, and other zeros, and to use Descartes’
5.6 – Quadratic Equations and Complex Numbers Objectives: Classify and find all roots of a quadratic equation. Graph and perform operations on complex.
Warm Up. Find all zeros. Graph.. TouchesThrough More on Rational Root Theorem.
Using the Fundamental Theorem of Algebra 6.7. Learning Targets Students should be able to… -Use fundamental theorem of algebra to determine the number.
Complex Numbers, Division of Polynomials & Roots.
Topic: U4L5 Remainder and Factor Theorems EQ: Can I correctly apply the Remainder and Factor Theorems to help me factor higher order polynomials?
7.4 Solving Polynomial Equations
Warm-Up Exercises 1. What is the degree of f (x) = 8x 6 – 4x 5 + 3x ? 2. Solve x 2 – 2x + 3 = 0 ANSWER 6 1 i 2 + _.
Theorems About Roots of Polynomial Equations. Find all zeros: f(x)= x +x –x Synthetic Division one zero…need 2 more use (x – k), where.
The Rational Zero Theorem The Rational Zero Theorem gives a list of possible rational zeros of a polynomial function. Equivalently, the theorem gives all.
FACTOR to SOLVE 1. X 2 – 4x X 2 – 17x + 52 (x-10)(x + 6) x = 10, -6 (x-4)(x - 13) x = 4,13.
Solving Polynomial Equations by Factoring Factoring by grouping Ex. 1. Solve:
6.5 Theorems About Roots of Polynomial Equations
LESSON 5.6 Rational Zeros of Polynomial Functions.
Remainder and Factor Theorems
Chapter 4: Polynomial and Rational Functions. 4-2 Quadratic Equations For a quadratic equation in the form ax 2 + bx + c = 0 The quadratic Formula is.
EXAMPLE 3 Find zeros when the leading coefficient is not 1
Real Zeros of Polynomial Functions. Solve x 3 – 2x + 1 = 0. How? Can you factor this? Can you use the quadratic formula? Now what if I tell you that one.
Section 3.4 Zeros of Polynomial Functions. The Rational Zero Theorem.
Chapter 2 – Polynomial and Rational Functions 2.5 – The Fundamental Theorem of Algebra.
Algebra 2 List all the integer factors for the number below: 36.
Zeros (Solutions) Real Zeros Rational or Irrational Zeros Complex Zeros Complex Number and its Conjugate.
Algebra 2. Solve for x Algebra 2 (KEEP IN MIND THAT A COMPLEX NUMBER CAN BE REAL IF THE IMAGINARY PART OF THE COMPLEX ROOT IS ZERO!) Lesson 6-6 The Fundamental.
Section 2.5 – Quadratic Equations
Warm-ups Week 8 10/8/12 Find the zeros of f(x) = x3 + 2x2 – 13x + 10 algebraically (without a graphing calculator). What if I told.
Section 3.4 Zeros of Polynomial Functions
2.5 Zeros of Polynomial Functions
Real Zeros Intro - Chapter 4.2.
4.2 Real Zeros Finding the real zeros of a polynomial f(x) is the same as solving the related polynomial equation, f(x) = 0. Zero, solution, root.
5 solutions/zeros Number of Solutions is... … degree of Polynomial
Warm - Up Perform the operation and write the result in standard form
5.6 Find The Rational Zeros
Rational Root Theorem Math 3 MM3A1.
Finding polynomial roots
Lesson 2.5 The Fundamental Theorem of Algebra
Creating Polynomials Given the Zeros.
Warm-up: Find all real solutions of the equation X4 – 3x2 + 2 = 0
Rational Root Theorem.
A few more things about graphing and zeros.
FINDING ROOTS WITHOUT A CLUE
Roots & Zeros of Polynomials III
1) Find f(g(x)) and g(f(x) to show that f(x) and g(x) are inverses
Bell Ringer (in your Math Journal)
Presentation transcript:

7.4-7.6

Writing Equations from Roots (Remember that the conjugate is also a root) Double root at -2/3, root at 0, and root at 2i So -2i is also a root (x-0)(x + 2/3) (x + 2/3) (x – 2i) (x + 2i) (x)(3x + 2) (3x + 2) (x – 2i) (x + 2i) (x)(9x2 + 12x + 4)(x – 4i2)(x2 + 4) (x)(9x4 +12x3+ + 40x2 + 48x + 16) Y=(9x5 + 12x4 + 40x3 + 48 x2 + 16x)

3+4i and 2 are roots (x – 2) (x – (3 + 4i)(x – (3 – 4i)) +16 (x – 2) (x2 -3x + 4ix – 3x + 9 – 12i – 4ix + 12i – 16i2 ) (x – 2) (x2 -6x + 25) (x3 -6x2 + 25x – 2x2 + 12x- 50) Y = x3 - 8x2 + 37x - 50

Possible Rational Zeros Possible rational zeros: Factors of Constant Factors of lead. coeff Ex: Find possible rational zeros of: 3x4 + ……… + 14 1,2,7,14 1, 3 + { 1, 2, 7, 14, 1/3, 2/3, 7/3, 14/3}

Division X6 + ………. 12 = (x + ~)(x5 + ………) (x+~)(x4 + ……) 150 75 3 25 5 5 X6 + ………. 12 = (x + ~)(x5 + ………) (x+~)(x4 + ……) (x+~)(x3 + ……) (x + ~)(x2 + ~~~~~) Quad. formula If it’s x6 then find 4 zeros and divide 4 times until x2 If it’s x3 then find 1 zero and divide 1 time until x2

Finding possible rational zeros, zeros and factors 1,2,5,10,2550 1 +1, + 2 +,5, + 10, + 50,+ 25 Y = x3 -8x2 + 37x - 50 Graph to find root(s)… Root is at 2 so 1 real, 2 imaginary 1 - 8 37 -50 0 2 -12 50 1 -6 25 0 Factors (x – 2)(X2 -6x + 25) This means that f(2) = 0 X2 -6x + 25 Not factorable so use Q.formula…… 3 + 4i and 3 – 4i Zeros: 2, 3 + 4i, 3 – 4i

G(x) = 48x4 - 52x3 + 13x - 3 Possible Rational : 1, 3 Zeros 1,2,3,4,6,8,12,16, 24,48 +{1, 1/2, 1/3, 1/4, 1/6, 1/8, 1/12, 1/6,1/24, 1/48, 3, 3/2, ¾, 3/8, 3/16} Graph and zeros are at -1/2, ½, ¾, 1/3 -1/2 48 - 52 0 13 -3 0 -24 38 -19 3 48 -76 38 -6 0 This is 48x3 so keep going ½ 0 24 -26 6 48 -52 12 0 (x + ½)(x – ½)4(4x – 3)(3x – 1) (2x + 1)(2x – 1)(4x-3)(3x – 1) 48X2 -52x + 12  4(12x2 -13x + 3) 4(4x – 3)(3x – 1)  1/3 and ¾ or Q.F

Using synthetic to find f(~) Just use ~ in synthetic substitution Given a factor (x + #), find other factors Just use -~ in synthetic substitution -2 1 0 -3 3 0 -2 4 2 1 -2 -1 5 so it’s 5. F(x) = x3 - 3x + 3. Find f(-2) using synthetic substitution 3x – 2 is a factor of 6x3 – 25x2 + 2x + 8 find other factors so 3x – 2 = 0 3x = 2 x = 2/3 2/3 6 -25 2 8 4 -14 -8 6 -21 -12 0 6x2 -21x – 12 3(2x2 – 7x – 4) (2x + 1)(x – 4)