Download presentation
Presentation is loading. Please wait.
Published bySybil Washington Modified over 9 years ago
1
Slide 7- 1 Copyright © 2012 Pearson Education, Inc.
2
5.1 Introduction to Polynomials and Polynomial Functions ■ Terms and Polynomials ■ Degree and Coefficients ■ Polynomial Functions ■ Graphs of Polynomial Functions ■ Adding Polynomials ■ Opposites and Subtraction
3
Slide 5- 3 Copyright © 2012 Pearson Education, Inc. Characteristics of Polynomial Functions The graph of a polynomial function is “smooth”, that is, there are no sharp corners. The graph of a polynomial function is continuous, that is, there are no holes or breaks. The domain of a polynomial function, unless otherwise specified, is all real numbers. The domain of a polynomial function is (–∞, ∞).
4
Slide 5- 4 Copyright © 2012 Pearson Education, Inc. Algebraic Expressions and Polynomials A term can be a number, a variable, a product of numbers and/or variables, or a quotient of numbers and/or variables. A term that is a product of constants and/or variables is called a monomial. Examples of monomials: 8, w, 24 x 3 y A polynomial is a monomial or a sum of monomials. Examples of polynomials: 5w + 8, 3x 2 + x + 4, x, 0, 75y 6
5
Slide 5- 5 Copyright © 2012 Pearson Education, Inc. The leading term of a polynomial is the term of highest degree. Its coefficient is called the leading coefficient and its degree is referred to as the degree of the polynomial. Consider this polynomial 4x 2 9x 3 + 6x 4 + 8x 7. The terms are 4x 2, 9x 3, 6x 4, 8x, and 7. The coefficients are 4, 9, 6, 8 and 7. The degree of each term is 2, 3, 4, 1, and 0. The leading term is 6x 4 and the leading coefficient is 6. The degree of the polynomial is 4.
6
Slide 5- 6 Copyright © 2012 Pearson Education, Inc. A polynomial that is composed of two terms is called a binomial, whereas those composed of three terms are called trinomials. Polynomials with four or more terms have no special name. MonomialsBinomialsTrinomialsPolynomials 5x25x2 3x + 43x 2 + 5x + 9 5x 3 6x 2 + 2xy 9 84a 5 + 7bc 7x 7 9z 3 + 5a 4 + 2a 3 a 2 + 7a 2 8a 23 b 3 10x 3 76x 2 4x ½6x 6 4x 5 + 2x 4 x 3 + 3x 2
7
Slide 5- 7 Copyright © 2012 Pearson Education, Inc. Polynomial Functions If the polynomial describing a function has degree 1, we say that the function is linear. A quadratic function is described by a polynomial of degree 2, a cubic function by a polynomial of degree 3,and a quartic function by a polynomial of degree 4.
8
Slide 5- 8 Copyright © 2012 Pearson Education, Inc. Example Find P( 3) for the polynomial function given by P(x) = x 3 + 4x + 7. Solution P( 3) = ( 3) 3 + 4( 3) + 7 = ( 27) + 4( 3) + 7 = 27 + ( 12) + 7 = 22
9
Slide 5- 9 Copyright © 2012 Pearson Education, Inc. Example In a sports league of n teams in which each team plays every other team twice, the total number of games to be played is given by the polynomial n 2 n. A boys’ soccer league has 12 teams. How many games are played if each team plays every other team twice? Solution We evaluate the polynomial for n = 12: n 2 n = 12 2 12 = 144 12 = 132. The league plays 132 games.
10
Slide 5- 10 Copyright © 2012 Pearson Education, Inc. Example The average number of accidents per day involving drivers of age r can be approximated by the polynomial f(r) = 0.4r 2 40r + 1039. Find the average number of accidents per day involving 25-year- old drivers. Solution f(25) = 0.4(25) 2 40(25) + 1039 = 0.4(625) 1000 + 1039 = 250 1000 + 1039 = 289 There are, on average, approximately 289 accidents each day involving 25-year-old drivers.
11
Slide 5- 11 Copyright © 2012 Pearson Education, Inc. Graph the polynomial function in the standard view and estimate the range of the graph. f(x) = x 3 – 3x 2 + 1 Solution Example The range is all real numbers.
12
Slide 5- 12 Copyright © 2012 Pearson Education, Inc. Adding Polynomials
13
Slide 5- 13 Copyright © 2012 Pearson Education, Inc. Example Combine like terms. a) 4y 4 9y 4 b) 7x 5 + 9 + 3x 2 + 6x 2 13 6x 5 c) 9w 5 7w 3 + 11w 5 + 2w 3 Solution a) 4y 4 9y 4 = (4 9)y 4 = 5y 4 b) 7x 5 + 9 + 3x 2 + 6x 2 13 6x 5 = 7x 5 6x 5 + 3x 2 + 6x 2 + 9 13 = x 5 + 9x 2 4 c) 9w 5 7w 3 + 11w 5 + 2w 3 = 9w 5 + 11w 5 7w 3 + 2w 3 = 20w 5 5w 3 Adding Polynomials
14
Slide 5- 14 Copyright © 2012 Pearson Education, Inc. Example Add: ( 6x 3 + 7x 2) + (5x 3 + 4x 2 + 3). Solution ( 6x 3 + 7x 2) + (5x 3 + 4x 2 + 3) = ( 6 + 5)x 3 + 4x 2 + 7x + ( 2 + 3) = x 3 + 4x 2 + 7x + 1
15
Slide 5- 15 Copyright © 2012 Pearson Education, Inc. Add: (3 4x + 2x 2 ) + ( 6 + 8x 4x 2 + 2x 3 ). Solution (3 4x + 2x 2 ) + ( 6 + 8x 4x 2 + 2x 3 ) = (3 6) + ( 4 + 8)x + (2 4)x 2 + 2x 3 = 3 + 4x 2x 2 + 2x 3 Example
16
Slide 5- 16 Copyright © 2012 Pearson Education, Inc. Add: 10x 5 3x 3 + 7x 2 + 4 and 6x 4 8x 2 + 7 and 4x 6 6x 5 + 2x 2 + 6 Solution 10x 5 3x 3 + 7x 2 + 4 6x 4 8x 2 + 7 4x 6 6x 5 + 2x 2 + 6 4x 6 + 4x 5 + 6x 4 3x 3 + x 2 + 17 The answer is 4x 6 + 4x 5 + 6x 4 3x 3 + x 2 + 17. Example
17
Slide 5- 17 Copyright © 2012 Pearson Education, Inc. The Opposite of a Polynomial The opposite of a polynomial P can be written as ‒ P or, equivalently, by replacing each terms with its opposite.
18
Slide 5- 18 Copyright © 2012 Pearson Education, Inc. Simplify: ( 8x 4 x 3 + 9x 2 2x + 72). Solution ( 8x 4 x 3 + 9x 2 2x + 72) = 8x 4 + x 3 9x 2 + 2x 72 Example
19
Slide 5- 19 Copyright © 2012 Pearson Education, Inc. (10x 5 + 2x 3 3x 2 + 5) ( 3x 5 + 2x 4 5x 3 4x 2 ). Solution (10x 5 + 2x 3 3x 2 + 5) ( 3x 5 + 2x 4 5x 3 4x 2 ) = 10x 5 + 2x 3 3x 2 + 5 + 3x 5 2x 4 + 5x 3 + 4x 2 = 13x 5 2x 4 + 7x 3 + x 2 + 5 Example Subtract:
20
Slide 5- 20 Copyright © 2012 Pearson Education, Inc. Subtract: (8x 5 + 2x 3 10x) (4x 5 5x 3 + 6). Solution (8x 5 + 2x 3 10x) (4x 5 5x 3 + 6) = 8x 5 + 2x 3 10x + ( 4x 5 ) + 5x 3 6 = 4x 5 + 7x 3 10x 6 Example
21
Slide 5- 21 Copyright © 2012 Pearson Education, Inc. Write in columns and subtract: (6x 2 4x + 7) (10x 2 6x 4). Solution 6x 2 4x + 7 (10x 2 6x 4) 4x 2 + 2x + 11 Example
Similar presentations
© 2025 SlidePlayer.com Inc.
All rights reserved.