MA 105 Week 7 Assignment 20/20 Correct Answers

 

 

QUESTION 1

 

Evaluate the function at the indicated value of x.  Round your result to three decimal places.

Function: f(x) = 0.5x   Value: x = 1.7

 

    -0.308
    1.7
    0.308
    0.5
    -1.7

 

 

QUESTION 2

 

Match the graph with its exponential function.

 

    y = 2-x – 3
    y = -2x + 3
    y = 2x + 3
    y = 2x – 3
    y = -2x – 3

 

 

QUESTION 3

 

Select the graph of the function.

f(x) = 5x-1

 

     
     
     
     
     

 

 

QUESTION 4

 

Evaluate the function at the indicated value of x.  Round your result to three decimal places.

Function: f(x) = 500e0.05x    Value: x=17

 

    1169.823
    1369.823
    1569.823
    1269.823
    1469.823

 

 

QUESTION 5

Use the One-to-One property to solve the equation for x.

e3x+5 = 36

 

    x = –1/3
    x2 = 6
    x = -3
    x = 1/3
    x = 3

 

 

QUESTION 6

Write the logarithmic equation in exponential form.

log8 64 = 2

 

    648 = 2
    82 = 16
    82 = 88
    82 = 64
    864 = 2

 

 

QUESTION 7

Write the logarithmic equation in exponential form.

log7 343 = 3

 

    7343 = 2
    73 = 77
    73 = 343
    73 = 14
    3437 = 2

 

 

QUESTION 8

Write the exponential equation in logarithmic form.

43 = 64

    log64 4 = 3
    log4 64 = 3
    log4 64 = -3
    log4 3 = 64
    log4 64 = 1/3

 

 

QUESTION 9

Use the properties of logarithms to simplify the expression.

log20 209

    0
    1/9
    1/9
    -9
    9

 

 

QUESTION 10

Use the One-to-One property to solve the equation for x.

log2(x+4) = log2 20

    19
    17
    18
    16
    20

 

 

QUESTION 11

Find the exact value of the logarithmic expression.

log6 36

    2
    6
    36
    -2
    none of these

 

 

QUESTION 12

Use the properties of logarithms to expand the expression as a sum, difference, and/or constant multiple of logarithms.  (Assume all variables are positive.)

log3 9x

     
    log3 9 x log3 x
    log3 9 + log3 x
    log3 9 log3
    none of these

 

 

QUESTION 13

Condense the expression to a logarithm of a single quantity. 

logx – 2logy + 3logz

     
     
     
     
     

 

 

QUESTION 14

Evaluate the logarithm using the change-of-base formula.  Round your result to three decimal places.

log4 9

    1.585
    5.585
    3.585
    4.585
    2.585

 

 

QUESTION 15

Determine whether the given x-value is a solution (or an approximate solution) of the equation.

42x-7 = 16

x = 5

    no
    yes

 

 

QUESTION 16

Solve for x.

3x = 81

    7
    3
    4
    -4
    -3

 

 

QUESTION 17

Solve the exponential equation algebraically.  Approximate the resulted to three decimal places.

e5x = ex2-14

    -7, -2
    7, -2
    5, -14
    7, 2
    -7, 2

 

 

QUESTION 18

Solve the logarithmic equation algebraically.  Approximate the result to three decimal places.

log3(6x-8) = log3(5x + 10)

    18
    20
    17
    19
    -2

 

 

QUESTION 19

Find the magnitude R of each earthquake of intensity I (let I0=1).

I = 19000

    3.28
    5.28
    4.28
    2.38
    6.28

 

 

 

QUESTION 20

$2500 is invested in an account at interest rate r, compounded continuously.  Find the time required for the amount to double.  (Approximate the result to two decimal places.)

r = 0.0570

    13.16 years
    10.16 years
    11.16 years
    12.16 years
    14.16 years