1 © 2010 Pearson Education, Inc. All rights reserved © 2010 Pearson Education, Inc. All rights reserved Chapter 3 Polynomial and Rational Functions.

Slides:



Advertisements
Similar presentations
Notes 6.6 Fundamental Theorem of Algebra
Advertisements

SECTION 3.6 COMPLEX ZEROS; COMPLEX ZEROS; FUNDAMENTAL THEOREM OF ALGEBRA FUNDAMENTAL THEOREM OF ALGEBRA.
Zeros of Polynomial Functions Section 2.5. Objectives Use the Factor Theorem to show that x-c is a factor a polynomial. Find all real zeros of a polynomial.
Zeros of Polynomial Functions
1 5.6 Complex Zeros; Fundamental Theorem of Algebra In this section, we will study the following topics: Conjugate Pairs Theorem Finding a polynomial function.
Solving Polynomial Equations. Fundamental Theorem of Algebra Every polynomial equation of degree n has n roots!
Section 5.6 – Complex Zeros; Fundamental Theorem of Algebra Complex Numbers Standard form of a complex number is: a + bi. Every complex polynomial function.
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.
Warm up Use the Rational Root Theorem to determine the Roots of : x³ – 5x² + 8x – 6 = 0.
The Fundamental Theorem of Algebra And Zeros of Polynomials
Sullivan Algebra and Trigonometry: Section 5.6 Complex Zeros; Fundamental Theorem of Algebra Objectives Utilize the Conjugate Pairs Theorem to Find the.
Copyright © 2006 Pearson Education, Inc. Publishing as Pearson Addison-Wesley The Fundamental Theorem of Algebra ♦ Perform arithmetic operations on complex.
Copyright © Cengage Learning. All rights reserved. 2 Polynomial and Rational Functions.
College Algebra Sixth Edition James Stewart Lothar Redlin Saleem Watson.
Complex Zeros; Fundamental Theorem of Algebra
9.9 The Fundamental Theorem of Algebra
Copyright © 2014, 2010 Pearson Education, Inc. Chapter 2 Polynomials and Rational Functions Copyright © 2014, 2010 Pearson Education, Inc.
Zeros of Polynomial Functions Section 2.5 Page 312.
Precalculus Complex Zeros V. J. Motto. Introduction We have already seen that an nth-degree polynomial can have at most n real zeros. In the complex number.
Copyright © 2013, 2009, 2005 Pearson Education, Inc. 1 3 Polynomial and Rational Functions Copyright © 2013, 2009, 2005 Pearson Education, Inc.
The Rational Root Theorem.  Is a useful way to find your initial guess when you are trying to find the zeroes (roots) of the polynomial.  THIS IS JUST.
Chapter 3 Polynomial and Rational Functions Copyright © 2014, 2010, 2007 Pearson Education, Inc Zeros of Polynomial Functions.
6.6 The Fundamental Theorem of Algebra
General Results for Polynomial Equations In this section, we will state five general theorems about polynomial equations, some of which we have already.
Slide Copyright © 2007 Pearson Education, Inc. Publishing as Pearson Addison-Wesley.
3.4 Zeros of Polynomial Functions. The Fundamental Theorem of Algebra If f(x) is a polynomial of degree n, where n>0, then f has at least one zero in.
Zeros of Polynomials 2.5.
Section 3.3 Theorems about Zeros of Polynomial Functions.
Warm Up. Find all zeros. Graph.. TouchesThrough More on Rational Root Theorem.
Copyright © 2009 Pearson Education, Inc. CHAPTER 4: Polynomial and Rational Functions 4.1 Polynomial Functions and Models 4.2 Graphing Polynomial Functions.
Section 4.4 Theorems about Zeros of Polynomial Functions Copyright ©2013, 2009, 2006, 2001 Pearson Education, Inc.
Using the Fundamental Theorem of Algebra 6.7. Learning Targets Students should be able to… -Use fundamental theorem of algebra to determine the number.
Chapter 2 Polynomial and Rational Functions. Warm Up
Copyright © 2007 Pearson Education, Inc. Publishing as Pearson Addison-Wesley Slide 2- 1.
The Fundamental Theorem of Algebra It’s in Sec. 2.6a!!! Homework: p odd, all.
Fundamental Theorem of Algebra Every polynomial function of positive degree with complex coefficients has at least one complex zero.
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall. Section 5.6 Complex Zeros; Fundamental Theorem of Algebra.
Copyright © 2011 Pearson, Inc. 2.5 Complex Zeros and the Fundamental Theorem of Algebra.
Chapter 3 Polynomial and Rational Functions Copyright © 2014, 2010, 2007 Pearson Education, Inc Zeros of Polynomial Functions.
5.6 The Fundamental Theorem of Algebra. If P(x) is a polynomial of degree n where n > 1, then P(x) = 0 has exactly n roots, including multiple and complex.
1/27/2016 Math 2 Honors - Santowski 1 Lesson 21 – Roots of Polynomial Functions Math 2 Honors - Santowski.
Section 4.6 Complex Zeros; Fundamental Theorem of Algebra.
7.5 Roots and Zeros Objectives:
The Fundamental Theorem of Algebra Intro - Chapter 4.6.
2.5 The Fundamental Theorem of Algebra. The Fundamental Theorem of Algebra The Fundamental Theorem of Algebra – If f(x) is a polynomial of degree n, where.
Every polynomial P(x) of degree n>0 has at least one zero in the complex number system. N Zeros Theorem Every polynomial P(x) of degree n>0 can be expressed.
Chapter 2 – Polynomial and Rational Functions 2.5 – The Fundamental Theorem of Algebra.
Section 2.5. Objectives:  Use the Fundamental Theorem of Algebra to determine the number of zeros of a polynomial function.  Find all zeros of polynomial.
Fundamental Theorem of Algebra
Section 6.6 The Fundamental Theorem of Algebra
Warm-up Multiply the factors and write in standard form.
Fundamental Theorem of Algebra
Lesson 7.2: Finding Complex Solutions of Polynomial Equations
3.8 Complex Zeros; Fundamental Theorem of Algebra
Lesson 2.5 The Fundamental Theorem of Algebra
Copyright © 2014, 2010, 2007 Pearson Education, Inc.
Lesson 2.5 The Fundamental Theorem of Algebra
Fundamental Theorem of Algebra
Apply the Fundamental Theorem of Algebra
The Fundamental Theorem of Algebra
3.4 Zeros of Polynomial Functions: Real, Rational, and Complex
Warm-up: Find all real solutions of the equation X4 – 3x2 + 2 = 0
4.6 - Fundamental Theorem of Algebra
Fundamental Theorem of Algebra
1) Find f(g(x)) and g(f(x) to show that f(x) and g(x) are inverses
Fundamental Theorem of Algebra
Copyright © Cengage Learning. All rights reserved.
Presentation transcript:

1 © 2010 Pearson Education, Inc. All rights reserved © 2010 Pearson Education, Inc. All rights reserved Chapter 3 Polynomial and Rational Functions

OBJECTIVES © 2010 Pearson Education, Inc. All rights reserved 2 The Complex Zeros of a Polynomial Function SECTION Learn basic facts about the complex zeros of polynomials. Use the Conjugate Pairs Theorem to find zeros of polynomials.

3 © 2010 Pearson Education, Inc. All rights reserved If we extend our number system to allow the coefficients of polynomials and variables to represent complex numbers, we call the polynomial a complex polynomial. If P(z) = 0 for a complex number z we say that z is a zero or a complex zero of P(x). In the complex number system, every nth-degree polynomial equation has exactly n roots and every nth-degree polynomial can be factored into exactly n linear factors. Definitions

4 © 2010 Pearson Education, Inc. All rights reserved FUNDAMENTAL THEOREM OF ALGEBRA Every polynomial with complex coefficients a n, a n – 1, …, a 1, a 0 has at least one complex zero.

5 © 2010 Pearson Education, Inc. All rights reserved FACTORIZATION THEOREM FOR POLYNOMIALS If P(x) is a complex polynomial of degree n ≥ 1, it can be factored into n (not necessarily distinct) linear factors of the form where a, r 1, r 2, …, r n are complex numbers.

6 © 2010 Pearson Education, Inc. All rights reserved NUMBER OF ZEROS THEOREM Any polynomial of degree n has exactly n zeros, provided a zero of multiplicity k is counted k times.

7 © 2010 Pearson Education, Inc. All rights reserved EXAMPLE 1 Constructing a Polynomial Whose Zeros are Given Find a polynomial P(x) of degree 4 with a leading coefficient of 2 and zeros –1, 3, i, and –i. Write P(x) Solution a. Since P(x) has degree 4, we write a.in completely factored form; b.by expanding the product found in part a.

8 © 2010 Pearson Education, Inc. All rights reserved EXAMPLE 1 Constructing a Polynomial Whose Zeros are Given Solution continued b. Expand the product found in part a.

9 © 2010 Pearson Education, Inc. All rights reserved CONJUGATE PAIRS THEOREM If P(x) is a polynomial function whose coefficients are real numbers and if z = a + bi is a zero of P, then its conjugate, is also a zero of P.

10 © 2010 Pearson Education, Inc. All rights reserved ODD–DEGREE POLYNOMIALS WITH REAL ZEROS Any polynomial P(x) of odd degree with real coefficients must have at least one real zero.

11 © 2010 Pearson Education, Inc. All rights reserved EXAMPLE 2 Using the Conjugate Pairs Theorem A polynomial P(x) of degree 9 with real coefficients has the following zeros: 2, of multiplicity 3; 4 + 5i, of multiplicity 2; and 3 – 7i. Write all nine zeros of P(x). 2, 2, 2, 4 + 5i, 4 – 5i, 4 + 5i, 4 – 5i, 3 + 7i, 3 – 7i Solution Since complex zeros occur in conjugate pairs, the conjugate 4 – 5i of 4 + 5i is a zero of multiplicity 2, and the conjugate 3 + 7i of 3 – 7i is a zero of P(x). The nine zeros of P(x) are:

12 © 2010 Pearson Education, Inc. All rights reserved FACTORIZATION THEOREM FOR A POLYNOMIAL WITH REAL COEFFICIENTS Every polynomial with real coefficients can be uniquely factored over the real numbers as a product of linear factors and/or irreducible quadratic factors.

13 © 2010 Pearson Education, Inc. All rights reserved EXAMPLE 3 Finding the Complex Real Zeros of a Polynomial Given that 2 – i is a zero of Solution The conjugate of 2 – i, 2 + i is also a zero. So P(x) has linear factors: find the remaining zeros.

14 © 2010 Pearson Education, Inc. All rights reserved EXAMPLE 3 Finding the Complex Real Zeros of a Polynomial Solution continued Divide P(x) by x 2 – 4x + 5.

15 © 2010 Pearson Education, Inc. All rights reserved EXAMPLE 3 Finding the Complex Real Zeros of a Polynomial Solution continued Therefore The zeros of P(x) are 1 (of multiplicity 2), 2 – i, and 2 + i.

16 © 2010 Pearson Education, Inc. All rights reserved EXAMPLE 4 Finding the Zeros of a Polynomial Find all zeros of the polynomial P(x) = x 4 – x 3 + 7x 2 – 9x – 18. Solution Possible zeros are: ±1, ±2, ±3, ±6, ±9, ±18 Use synthetic division to find that 2 is a zero. (x – 2) is a factor of P(x). Solve

17 © 2010 Pearson Education, Inc. All rights reserved EXAMPLE 4 Finding the Zeros of a Polynomial Solution continued The four zeros of P(x) are –1, 2, –3i, and 3i.