nth Roots and Rational Exponents (Part I) Read 5.1 ... · The function M(n)=0.75E(n) approximates...

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CC Algebra II HW #32 n th Roots and Rational Exponents (Part I) Read 5.1 Examples 1-3 Section 5.1 1. Vocabulary Rewrite the expression t s a in radical form. Then state the index of the radical. 2. Complete the Sentence For an integer n greater than 1, if a b n = , then b is a(n) __________________ of a. 4. Which One Doesn’t Belong? Which expression does not belong with the other three? Explain your reasoning. In Exercises 5–10, find the indicated real nth root(s) of a. (See Example 1.) 5. n = 3, a = 8 7. n = 2, a = 0 9. n = 5, a = –32 Evaluate the expression without using a calculator. (See Example 2.) 13. 2 3 25 15. 5 1 ) 243 (17. 3 2 8 Error Analysis Describe and correct the error in evaluating the expression. 19. Name ____________________________ Period ___ Row___ Date ___________

Transcript of nth Roots and Rational Exponents (Part I) Read 5.1 ... · The function M(n)=0.75E(n) approximates...

Page 1: nth Roots and Rational Exponents (Part I) Read 5.1 ... · The function M(n)=0.75E(n) approximates the distance a pilot can see to the horizon n feet above the surface of Mars. Write

CC Algebra II HW #32

nth Roots and Rational Exponents (Part I) Read 5.1 Examples 1-3

Section 5.1

1. Vocabulary Rewrite the expression ts

a−

in radical form. Then state the index of the radical. 2. Complete the Sentence For an integer n greater than 1, if abn = , then b is a(n) __________________ of a. 4. Which One Doesn’t Belong? Which expression does not belong with the other three? Explain your reasoning.

In Exercises 5–10, find the indicated real nth root(s) of a. (See Example 1.) 5. n = 3, a = 8 7. n = 2, a = 0 9. n = 5, a = –32 Evaluate the expression without using a calculator. (See Example 2.)

13. 23

25 15. 51

)243(− 17. 32

8− Error Analysis Describe and correct the error in evaluating the expression. 19.

Name ____________________________

Period ___ Row___ Date ___________

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Using Structure In Exercises 21–24, match the equivalent expressions. Explain your reasoning.

21. ( )43 5 A. 41

5−

22. ( )34 5 B. 34

5

23. 4 51 C. 4

1

5−

24. 4 5− D. 43

5 Evaluate the expression using a calculator. Round your answer to two decimal places when appropriate. (See Example 3.)

27. 31

25− 47. Number Sense Between which two consecutive integers does 4 125 lie? Explain your reasoning. 49. Problem Solving A weir is a dam that is built across a river to regulate the flow of water. The flow rate Q (in cubic

feet per second) can be calculated using the formula 23

367.3 hQ != , where ! is the length (in feet) of the bottom of the spillway and h is the depth (in feet) of the water on the spillway. Determine the flow rate of a weir with a spillway that is 20 feet long and has a water depth of 5 feet.

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CC Algebra II HW #33

Properties of Rational Exponents Properties of Radicals (Part I)

Read 5.2 Examples 1-2 Section 5.2 In Exercises 3–12, use the properties of rational exponents to simplify the expression. (See Example 1.)

3. ( )3129 5. 41

6

6 7. 41

4

4

108

⎟⎟⎠

⎞⎜⎜⎝

9. 1

31

32

33−

−⎟⎠⎞⎜

⎝⎛ • 11.

32

32

32

4

162 •

In Exercises 13–20, use the properties of radicals to simplify the expression. (See Example 2.)

13. 722 • 17. 5

5

2486

18. 322 19.

3

33

2726 •

74. Modeling With Mathematics

The surface area S (in square centimeters) of a mammal can be modeled by 32

kmS = , where m is the mass (in grams) of the mammal and k is a constant. The table shows the values of k for different mammals.

a. Find the surface area of a bat whose mass is 32 grams.

Name ____________________________

Period ___ Row___ Date ___________

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CC Algebra II HW #34

Properties of Rational Exponents Properties of Radicals (Part II)

Read 5.2 Examples 3, 4, 6 Section 5.2 2. Which One Doesn’t Belong? Which radical does not belong with the other three? Explain your reasoning.

In Exercises 21–28, write the expression in simplest form. (See Example 3.)

21. 4 567 23. 3

3

45

25. 83 27.

3

4964

In Exercises 29–36, write the expression in simplest form. (See Example 4.)

29. 31

1+

33. 73

9+

35. 53

6−

Name ____________________________

Period ___ Row___ Date ___________

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CC Algebra II HW #35

Properties of Rational Exponents Properties of Radicals (Part III)

Read 5.2 Examples 6 and 7 Section 5.2 Write the expression in simplest form. (See Example 4.)

31. 23

5−

Simplify the expression. (See Example 6.)

49. 4 881y 51. 5

5

10

nm 53.

6

7

6

hhg

Write the expression in simplest form. Assume all variables are positive. (See Example 7.)

57. 912781 cba 59. 5

7

6160nm

61. 16

53

25w

ww • 63.

21

34

45

31

27

18

vw

vw

Name ____________________________

Period ___ Row___ Date ___________

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78. How Do You See It?

Without finding points, match the functions 264)( xxf = and 3 664)( xxg = with their graphs. Explain your reasoning.

80. Thought Provoking

Determine whether the expressions ( )612x and 2

61

⎟⎠⎞⎜

⎝⎛ x are equivalent for all values of x.

Maintaining Mathematical Proficiency Write a rule for g. Describe the graph of g as a transformation of the graph of f. (Section 4.7) 87. 4)( 3 −= xxf , )2()( −= xfxg

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CC Algebra II HW #36

Graphing and Transforming Radical Functions Read 5.3 Examples 1-4

Section 5.3 1. Complete the Sentence Square root functions and cube root functions are examples of ________________ functions. 2. Complete the Sentence When graphing khxay +−= 3 , translate the graph of 3 xay = h units ______________ and k units ____________. In Exercises 3–8, match the function with its graph. 3. 3)( += xxf 4. 3)( += xxh 5. 3)( −= xxf 6. 3)( −= xxg 7. 33)( −+= xxh 8. 33)( +−= xxf Graph the function. Identify the domain and range of the function. (See Example 1.)

13. 3)( 51 −= xxg

Describe the transformation of f represented by g. Then graph each function. (See Example 2.)

21. 3)( xxf = , 1)( 3 −−= xxg 25. 4)( xxf = , 452)( 4 −+= xxg

Name ____________________________

Period ___ Row___ Date ___________

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28. Error Analysis Describe and correct the error in describing the transformation of the parent square root function represented by 3)( 2

1 += xxg .

39. Problem Solving The distance (in miles) a pilot can see to the horizon can be approximated by nnE 22.1)( = , where n is the plane’s altitude (in feet above sea level) on Earth. The function )(75.0)( nEnM = approximates the distance a pilot can see to the horizon n feet above the surface of Mars. Write a rule for M. What is the distance a pilot can see to the horizon from an altitude of 10,000 feet above Mars? (See Example 3.)

In Exercises 41 and 43, write a rule for g described by the transformations of the graph of f. (See Example 4.)

41. Let g be a vertical stretch by a factor of 2, followed by a translation 2 units up of the graph of 3)( += xxf . 43. Let g be a horizontal shrink by a factor of 3

2 , followed by a translation 4 units left of the graph of xxf 6)( = . Write a rule for g that represents the indicated transformation of the graph of f.

47. xxf 2)( = , )3()( += xfxg

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CC Algebra II HW #37-38

Solving Radical Equations Read 5.4 Examples 1-3 (and 4 for the challenge problem)

Section 5.4 In Exercises 3–12, solve the equation. Check your solution. (See Example 1.) 3. 615 =+x 7. 1113242 −=+− x 11. 15725 =+x 13. Modeling With Mathematics Biologists have discovered that the shoulder height h (in centimeters) of a male Asian elephant can be modeled by 8.755.62 3 += th , where t is the age (in years) of the elephant. Determine the age of an elephant with a shoulder height of 250 centimeters. (See Example 2.) Solve the equation. Check your solution(s). (See Examples 3 and 4.)

15. xx 36 =− 17. 10244 −=− xx

Name ____________________________

Period ___ Row___ Date ___________

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Solve the equation. Check your solution(s). (See Examples 3 and 4.)

19. 12183 3 −=− xx *25. 5183 +=+− xx (challenge problem) 57. Using Structure Explain how you know the radical equation 54 −=+x has no real solution without solving it. Maintaining Mathematical Proficiency Let 64)( 23 +−= xxxf . Write a rule for g. Describe the graph of g as a transformation of the graph of f. (Section 4.7) 70. 6)1()( +−−= xfxg

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CC Algebra II HW #39

Solving Equations with Rational Exponents Read 5.1 Examples 4-5, 5.4 Examples 5-6

Section 5.1 Mathematical Connections Find the radius of the figure with the given volume. 33. V = 216 ft3

Find the real solution(s) of the equation. Round your answer to two decimal places when appropriate. (See Example 4.) 37. 70)10( 5 =+x 41. 100366 =+x Section 5.2 79. Rewriting a Formula a. Solve the formula for the volume of a sphere, 3

34 rV π= , for r.

Name ____________________________

Period ___ Row___ Date ___________

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Section 5.4 In Exercises 27–34, solve the equation. Check your solution(s). (See Examples 5 and 6.)

27. 82 32

=x 29. 0341

=+x

31. xx =+ 21

)6( 33. 3)11(2 21

+=+ xx 36. Error Analysis Describe and correct the error in solving the equation.

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CC Algebra II HW #40-41

Inverses of Functions Read 5.6 Examples 1-6

Section 5.6 3. Complete the Sentence Functions f and g are inverses of each other provided that ___))(( =xgf and ___))(( =xfg . Solve y = f (x) for x. Then find the input(s) when the output is −3. (See Example 1.) 11. 7)2()( 2 −−= xxf Find the inverse of the function. Then graph the function and its inverse. (See Example 2.) 15. 52)( +−= xxf

Find the inverse of the function. Then graph the function and its inverse. (See Example 3.) 23. 24)( xxf = , 0≤x

Using Tools Use the graph to determine whether the inverse of f is a function. Explain your reasoning.

Name ____________________________

Period ___ Row___ Date ___________

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Determine whether the inverse of f is a function. Then find the inverse. (See Examples 4 and 5.) 35. 1)( 3 −= xxf 41. 2)( 4 += xxf 47. Writing Equations What is the inverse of the function whose graph is shown?

Determine whether the functions are inverses. (See Example 6.)

49. 92)( −= xxf , 92

)( +=xxg 51.

5

59)( +

=xxf , 95)( 5 −= xxg

59. Reasoning You and a friend are playing a number guessing game. You ask your friend to think of a positive number, square the number, multiply the result by 2, and then add 3. Your friend’s final answer is 53. What was the original number chosen? Justify your answer. Maintaining Mathematical Proficiency Describe the x-values for which the function is increasing, decreasing, positive, and negative. (Section 4.1) 77.