PreCalculus Honors: Functions and Their Graphs Honors: Functions and Their Graphs Semester 1, Unit...

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PreCalculus Honors: Functions and Their Graphs Semester 1, Unit 2: Activity 9 Resources: SpringBoard- PreCalculus Online Resources: PreCalculus SpringBoard Text Unit 2 Vocabulary: Efficiency Relative maximum Relative minimum Turning points Polynomial function End behavior Increasing Decreasing Multiplicity Multiple root Fundamental Theorem of Algebra Linear Factorization Theorem Rational Root Theorem Factor Theorem Remainder Theorem Descartes’ Rule of Signs Complex Conjugate Theorem Bounded Horizontal asymptote Vertical asymptote Parameter Hole Oblique asymptote Unit Overview In this unit, students study polynomial and rational functions. They graph these functions and find zeros. They explore complex factors of polynomial functions. Students also solve polynomial inequalities. Student Focus Main Ideas for success in lessons 9-1 & 9-2: Model data with polynomial functions. Compare models to best fit a data set. Describe and analyze graphs of polynomial functions. Graph polynomial functions and identify key features and end behavior of the graphs of polynomial functions. Example Lesson 9-1: Page 1 of 24

Transcript of PreCalculus Honors: Functions and Their Graphs Honors: Functions and Their Graphs Semester 1, Unit...

PreCalculus Honors: Functions and Their Graphs Semester 1, Unit 2: Activity 9

Resources:

SpringBoard-

PreCalculus

Online

Resources:

PreCalculus

SpringBoard Text

Unit 2

Vocabulary:

Efficiency Relative maximum Relative minimum Turning points Polynomial function End behavior Increasing Decreasing Multiplicity Multiple root Fundamental Theorem of Algebra Linear Factorization Theorem Rational Root Theorem Factor Theorem Remainder Theorem Descartes’ Rule of Signs Complex Conjugate

Theorem Bounded Horizontal asymptote Vertical asymptote Parameter Hole Oblique asymptote

Unit Overview

In this unit, students study polynomial and rational functions. They graph these functions and find zeros. They explore complex factors of polynomial functions. Students also solve polynomial inequalities.

Student Focus

Main Ideas for success in lessons 9-1 & 9-2:

Model data with polynomial functions.

Compare models to best fit a data set.

Describe and analyze graphs of polynomial functions.

Graph polynomial functions and identify key features and end behavior of the graphs of polynomial functions.

Example

Lesson 9-1:

Page 1 of 24

Lesson 9-2:

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PreCalculus Honors: Functions and Their Graphs Semester 1, Unit 2: Activity 10

Resources:

SpringBoard-

PreCalculus

Online

Resources:

PreCalculus

Springboard Text

Unit 2

Vocabulary:

Efficiency Relative maximum Relative minimum Turning points Polynomial function End behavior Increasing Decreasing Multiplicity Multiple root Fundamental Theorem

of Algebra Linear Factorization

Theorem Rational Root Theorem Factor Theorem Remainder Theorem Descartes’ Rule of Signs Complex Conjugate

Theorem Bounded Horizontal asymptote Vertical asymptote Parameter Hole Oblique asymptote

Unit Overview

In this unit, students study polynomial and rational functions. They graph these functions and find zeros. They explore complex factors of polynomial functions. Students also solve polynomial inequalities.

Student Focus

Main Ideas for success in lessons 10-1, 10-2, & 10-3

Use information about end behavior and min/max to sketch polynomial functions.

Use the Fundamental Theorem of Algebra and the Linear Factorization Theorem.

Use the Rational Root Theorem to find the zeros of a polynomial function.

Explore the Factor Theorem and the Remainder Theorem.

Example

Lesson 10-1: Difference of Squares Difference of Cubes Sum of Cubes

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Lesson 10-2:

1. Find factors of the leading coefficient, and the constant term, q.

2. Write all combinations of

.

3. Write all possible rational zeros.

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Use the Rational Root Theorem to find the possible real zeros and the Factor

Theorem to find the zeros.

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Lesson 10-3:

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PreCalculus Honors: Functions and Their Graphs Semester 1, Unit 2: Activity 11

Resources:

SpringBoard-

PreCalculus

Online

Resources:

PreCalculus

Springboard Text

Unit 2

Vocabulary:

Efficiency Relative maximum Relative minimum Turning points Polynomial function End behavior Increasing Decreasing Multiplicity Multiple root Fundamental Theorem

of Algebra Linear Factorization

Theorem Rational Root Theorem Factor Theorem Remainder Theorem Descartes’ Rule of Signs Complex Conjugate

Theorem Bounded Horizontal asymptote Vertical asymptote Parameter Hole Oblique asymptote

Unit Overview

In this unit, students study polynomial and rational functions. They graph these functions and find zeros. They explore complex factors of polynomial functions. Students also solve polynomial inequalities.

Student Focus

Main Ideas for success in lessons 11-1, 11-2, 11-3

Rewrite polynomials in factored form.

Find the zeros of a function, including zeros that are complex factors.

Solve polynomial inequalities.

Example Lesson 11-1:

The Complex Conjugate Theorem states that for a polynomial function with real

coefficients, if is a root, with and real numbers, then its complex

conjugate is also a root of the polynomial.

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Lesson 11-2:

The Zero Product Property says that for any product (a1)(a2)(a3) . . . (an) = 0, a1= 0

or a2 = 0 or a3 = 0 or . . . an = 0. This is true for polynomial factors as well as real

numbers.

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Page 10 of 24

Lesson 11-3:

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PreCalculus Honors: Functions and Their Graphs Semester 1, Unit 2: Activity 12

Resources:

SpringBoard-

PreCalculus

Online

Resources:

PreCalculus

Springboard Text

Unit 2

Vocabulary:

Efficiency Relative maximum Relative minimum Turning points Polynomial function End behavior Increasing Decreasing Multiplicity Multiple root Fundamental Theorem

of Algebra Linear Factorization

Theorem Rational Root Theorem Factor Theorem Remainder Theorem Descartes’ Rule of Signs Complex Conjugate

Theorem Bounded Horizontal asymptote Vertical asymptote Parameter Hole Oblique asymptote

Unit Overview

In this unit, students study polynomial and rational functions. They graph these functions and find zeros. They explore complex factors of polynomial functions. Students also solve polynomial inequalities.

Student Focus

Main Ideas for success in lessons 12-1 and 12-2

Will write rational expressions and rational functions that model real-world situations.

Examine asymptotic behaviors and sketch graphs of rational functions.

Emphasize end behaviors.

Example Lesson 12-1:

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Lesson 12-2:

The denominator will equal zero if were to equal ; therefore there is a

vertical asymptote at .

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PreCalculus Honors: Functions and Their Graphs Semester 1, Unit 2: Activity 13

Resources:

SpringBoard-

PreCalculus

Online

Resources:

PreCalculus

Springboard Text

Unit 2

Vocabulary:

Efficiency Relative maximum Relative minimum Turning points Polynomial function End behavior Increasing Decreasing Multiplicity Multiple root Fundamental Theorem

of Algebra Linear Factorization

Theorem Rational Root Theorem Factor Theorem Remainder Theorem Descartes’ Rule of Signs Complex Conjugate

Theorem Bounded Horizontal asymptote Vertical asymptote Parameter Hole Oblique asymptote

Unit Overview

In this unit, students study polynomial and rational functions. They graph these functions and find zeros. They explore complex factors of polynomial functions. Students also solve polynomial inequalities.

Student Focus

Main Ideas for success in lessons 13-1, 13-2, and 13-3.

Graph rational functions and transformations of rational functions.

Examine asymptotic behavior of rational functions.

Write functions involving rational equations and solve ration inequalitites.

Example Lesson 10-1:

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Lesson 13-2: Find the equation of the slant asymptote. Analyze the behavior of each function around its slant asymptote.

a.)

b.)

Lesson 13-3:

Write a function whose graph has an asymptote, the line , and a vertical asymptotes at .

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1© 2015 College Board. All rights reserved. SpringBoard Precalculus, Unit 2 Pratice

LeSSon 9-1 1. Examine the data in the table. What type of function could be used to model the data? Explain your reasoning.

University of XYZ

Year 2001 2002 2004 2006 2010 2011 2012 2014 2015 2016

number of enrolled Students

(in thousands)10 10.5 12 15.6 20.1 21.2 22.7 25 30.5 32.8

2. Model with mathematics. Use the regression capabilities of your graphing calculator to find a model that best represents the data in Item 1.

3. Attend to precision. Graph the equation you found in Item 2. List the important features of the graph. Approximate any values to three decimal places.

x

y

1050

15

25

35

45

20

30

40

50

210 3 4 5 7 96 8 10

4. Use the regression model to predict about how many students will be attending University XYZ in 2020.

A. 34,000

B. 36,000

C. 38,000

D. 2,899,000

5. Data are collected on puppies and their growth (by weight) over a 6-month period. What type of function could be used to model the data for the weight as a function of the number of months since the birth of a puppy? Explain your reasoning.

LeSSon 9-2 6. Which of the following functions is a fifth degree

polynomial?

A. f(x) 5 x(x 2 3)2(x 1 2)

B. f(x) 5 x2 1 2x(x 1 5)(x 2 7)

C. f(x) 5 (x 2 1)(x 1 9)3(x 2 2)

D. f(x) 5 x5(x 2 11)

Precalculus Unit 2 Practice

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7. Make use of structure. List the important features of the graph below. Approximate any values to three decimal places.

x

y

2122232425

25

24

23

22

21

1

2

3

4

5

1 2 3 4 5

8. Without using a calculator, determine the end behavior and x- and y-intercepts of the function f (x) 5 (2x 2 1)(x 1 1)(x 1 3).

9. Without using a calculator, find the end behavior, maximum possible zeros, and maximum possible turning points of the function f (x) 5 x6 2 2x3 1 1.

10. Use appropriate tools strategically. Use a graphing calculator to find the zeros, turning points, y-intercepts, and end behavior.

y 5 2x5 1 5.7x4 2 8x3 2 15x2 1 28

LeSSon 10-1 Make use of structure. For Items 11 and 12, determine the y-intercept and the end behavior of each function.

11. f(x) 5 7x7 2 8x5 1 3x4 1 2x2 21

12. h(x) 5 4(x 2 1)2(x 2 3)(x 1 2)

13. What are the zeros of the function f(x) 5 (x 1 2)4(x 2 3)5?

A. x 5 2, 23

B. x 5 22, 3

C. x 5 4, 5

D. x 5 24, 25

14. Attend to precision. Factor and find the zeros of the function. g(m) 5 m4 2 2m3 1 8m 216

15. Graph f(x) 5 (x 2 1)(x 1 5)2.

f(x)

x

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© 2015 College Board. All rights reserved. SpringBoard Precalculus, Unit 2 Pratice

LeSSon 10-2 16. Which of the following are possible zeros of

f(x) 5 3x4 1 x2 2 8?

A. 6 83

B. 6 32

C. 6 12

D. 6 163

17. Use the Rational Root Theorem to find the possible real zeros and the Factor Theorem to find the zeros of the function.

u(t) 5 3t3 2 5t2 1 6t 1 8

Make use of structure. For Items 18 and 19, use the Rational Root Theorem and synthetic division to find the real zeros.

18. f(x) 5 35x3 2 114x2 1 25x 1 6

19. g(x) 5 4x4 2 65x2 1 16

20. Use appropriate tools strategically. Use the Rational Root Theorem and a graphing calculator to find the rational root(s) of the polynomial.

f(x) 5 x4 2 5x 1 4

LeSSon 10-3 21. Which function has the greatest number of sign

changes?

A. f(x) 5 x7 2 10x6 1 40x5 2 96x4 1 176x3 2 224x2 2128x 2 1

B. g(x) 5 x7 2 10x6 2 40x5 2 96x4 1 176x3 2 224x2 2128x 2 1

C. h(x) 5 x7 1 10x6 1 40x5 2 96x4 2 176x3 1 224x2 2128x 1 1

D. j(x) 5 x7 1 10x6 1 40x5 1 96x4 1 176x3 1 224x2 1128x 2 1

Make use of structure. For Items 22 and 23, determine the number of positive and negative real zeros.

22. f(x) 5 2120x5 2 146x4 2 x3 1 27x2 1 x 2 1

23. f(x) 5 2150x3 1 153x 1 90

Attend to precision. For Items 24 and 25, sketch a graph of the polynomial function.

24. f(x) 5 x3 2 3x2 1 3x 21

f(x)

x

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© 2015 College Board. All rights reserved. SpringBoard Precalculus, Unit 2 Pratice

25. f(x) 5 2x4 2 3x3 2 2x2 1 3x 1 1f(x)

x

LeSSon 11-1 Orange Cell Phone Company is creating a package for their newest phone. The box package is made from cardboard pieces that are 14 inches long by 5 inches wide. The boxes are made by cutting a section of size x by x out of each corner of the cardboard.

26. Model with mathematics. Write the equation that represents the volume of the box.

27. a. Determine the possible domain and range for the construction of these boxes.

b. Sketch and label a graph of the volume function.

f(x)

x

28. Use a graphing calculator to find the maximum volume of a box that the Orange Cell Phone Company can make. What are the dimensions of the box with a maximum volume, and what is its volume?

29. Which polynomial has degree 6 and zeros x 5 26 2 1, 0,

12

, 1, 32

?

A. f (x) 5 (x 2 1)2(x 2 3)(x 1 1)(x 1 6)

B. f (x) 5 x(x 1 12)(x 1 1)(x 1

32)(x 2 1)(x 2 6)

C. f (x) 5 x(2x 11)(x 1 1)(2x 1 3)(x 2 1)(x 2 6)

D. f (x) 5 x(2x 21)(x 2 1)(2x 2 3)(x 1 1) (x 1 6)

30. Make use of structure. Find a polynomial with real coefficients of given degree with the given zeros.

degree: 4; zeros: x 5 21, 0, 3, 10

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LeSSon 11-2 31. Which of the following is a factor of the function

f (x) 5 2x2 2 8?

A. x 1 8 B. x 2 4

C. x 2 2 D. 2x 2 2

Make use of structure. For Items 32 and 33, rewrite each polynomial function as a product of complex factors.

32. f (x) 5 x2 1 144

33. g(x) 5 3x4 2 4x 2 7

Attend to precision. For Items 34 and 35, find the zeros of each function.

34. h (x) 5 x2 2 2x 1 3

35. r (x) 5 x4 1 27x

LeSSon 11-3 Model with mathematics. MetalBox Manufacturing also makes industrial air conditioning frames from an 8-foot-by-15-foot piece of metal. Square corners of length x are cut from each piece. The volume of the frame box must be at least 28 cubic feet.

36. Write an inequality for the volume that satisfies the constraint.

37. Use a graphing calculator to determine the interval over which the volume of the frame boxes made from the pieces of metal is larger than 28 cubic feet.

38. Use appropriate tools strategically. Using the piece of metal, what are the dimensions of the air conditioner with the largest possible volume?

A. 1.7 feet by 4.6 feet by 5.8 feet

B. 2 feet by 8 feet by 15 feet

C. 2 feet by 4 feet by 3.5 feet

D. 1.7 feet by 7.5 feet by 8 feet

Solve each inequality and write the solution interval.

39. x2 2 5x , 6

40. x4 $ 324

LeSSon 12-1 Model with mathematics. Student A and Student B are studying for the same test at the same rate. Both students studied through the dinner hour. Right now, Student B has been studying twice as many hours after the dinner hour as Student A. When both students study 1 more hour, Student B will have studied one and a half times as many hours from the dinner hour as Student A.

Let h represent Student A’s number of hours studied since the dinner hour.

41. Which equation can be used to find h, the current number of hours Student A has been studying?

A. h 5 h 1 1 B. h 1 1 5 1.5(h 1 1)

C. 2h 5 2h 1 1 D. 2h 1 1 5 1.5(h 1 1)

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42. Find the number of hours Student A has studied right now since the dinner hour.

43. Let S(x) represent the ratio of Student A’s number of hours studied since the dinner hour to Student B’s number of hours studied since the dinner hour, and let x represent the number of hours from now, either past or future. Write S as a function of x.

44. What appears to happen to the ratio of Student A’s number of hours since the dinner hour to Student B’s number of hours since the dinner hour as x increases?

45. Reason abstractly. If the two students keep studying at the same rate forever, would Student A ever catch up to Student B? Explain.

LeSSon 12-2

Model with mathematics. O(x) 5 xx

1013

1

1 represents

the ratio of Amy’s age in years to Michael’s age in years, where x represents the number of years from now, either past or future.

46. Sketch a graph of the function O(x) for 215 , x , 15.

y

x

47. Find the equation of the vertical asymptote of O(x).

A. x 5 1

B. x 5 21

C. x 5 13

D. x 5 213

48. Find the equation of the horizontal asymptote of O(x).

A. y 5 1

B. y 5 21

C. y 5 10

D. y 5 213

49. Demonstrate why the value of O(x) will never actually reach the value of the horizontal asymptote.

50. Use appropriate tools strategically. Use a graphing calculator to look at the behavior of the O(x) to the left of the vertical asymptote. Explain why you are not looking at that part of the graph for the given scenario.

y

x

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LeSSon 13-1 51. Consider the graphs for f(x) 5

x1 and g(x) 5

x1

52 .

Which of the following best describes the difference between the graphs of the two functions?

A. g(x) is a shift of f(x) to the left 5 units.

B. g(x) is a shift of f(x) to the right 5 units.

C. g(x) is a shift of f(x) up 5 units.

D. g(x) is a shift of f(x) down 5 units.

For Items 52 and 53, sketch a graph of each function.

52. h(x) 5 x

15 31

y

x

53. u(x) 5 x62

2 12

y

x

54. Attend to precision. Write to explain to another student how to obtain the graph of r(x) 5

x1

11 1 1

from the graph of f(x) 5 x1

.

55. express regularity in repeated reasoning. Write to explain to another student the similarities in the graphs of m(x) 5

x a11

1 b, n(x) 5 (x 1 a)2 1 b,

and o(x) 5 x a b1 1 when compared to the graphs of their respective parent functions.

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LeSSon 13-2 56. What is the horizontal asymptote of f(x) 5

xx

4 13 2

2

2

2

1 ?

A. y 5 0

B. y 5 12

C. y 5 43

D. y 5 34

57. What is the horizontal asymptote of

g(x) 5 x x x

x x x7 6 3

9 1 4

4 2

3 4

2 1

2 1 2?

A. y 5 0

B. y 5 79

C. y 5 32

D. y 5 13

58. Make use of structure. Find the equation of the slant asymptote of the function.

h(x) 5 x x

x5 3 1

1

2 2 1

2

59. Find the vertical asymptote and the point discontinuity in the graph of the function.

f (x) 5 x xx

2 381

2

4

2 1

2

60. Attend to precision. Sketch a graph of the function without using a graphing calculator.

p(x) 5 x

x3 4

13

1

2

y

x

LeSSon 13-3 Model with mathematics. For Items 61–63, write a possible function whose graph could have the following asymptotes.

61. y 5 24, x 5 3

62. y 5 0, x 5 61

63. y 5 212

x 1 1, x 5 0

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64. Which of the following functions could have a point of discontinuity at x 5 1?

A. f(x) 5 x

x 12

B. f(x) 5 x

x x1

( 1)( 1)2

2 1

C. f(x) 5 x

x x1

( 1)( 1)1

1 2

D. f(x) 5 x

x 1

2

2

65. Critique the reasoning of others. Kayla says that a function that is a rational expression has only vertical asymptotes where the factors in the denominator equal zero. Is she correct? If not, explain and correct her error.

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