A+ Answers


  Determine whether each of the following graphs represents a one-to-one
function.
2.       For each part below, determine if an inverse for the given f( x )
          exists.   If an inverse exists, then please find the inverse.  
         Otherwise, write “NO INVERSE”.      
 3.    In order to check to make sure we have the right inverse for a
       given f( x ), we can check that  and also that
       .    Using that idea of checking, please check to   
   make sure that the inverse you got in #2 (a) is the correct inverse
        for f( x ) = 3x + 3.
4.  The following formula can be used to convert Fahrenheit temperatures
     x to Celsius temperatures T(x):
                       
 Find T(-13)  and  T(86).
 Find T-1(x) and explain what it represents.
5.   Please choose which equation represents the following graph:

 f( x ) = -ex
 f( x ) = -ex + 1
 f( x ) = e-x + 1
6.  Please choose which equation represents the following graph:
 f( x ) = 2x - 1
 f( x ) = 2x - 1
 f( x ) = -2x - 1
 f( x ) = -2x – 1
7.  Water initially at 130 degrees Fahrenheit is left in a room of temperature
     70 degrees Fahrenheit to cool.   After t minutes, the temperature T of the
water is given by
                         
Find the temperature of the water 10 minutes after it is left to cool.
8.        Suppose that $100,000 is invested at 4% interest, compounded
 monthly.  Find the amount of money in the account after 10 years.
9.  Find each of the following, and round answer to the nearest 4 decimal places.
10.   Find log4 50 using the change of base formula, and round answer to the
        nearest 4 decimal places.
11.  Students in an accounting class took a final exam and then took equivalent
       forms of the exam at monthly intervals thereafter.   The average score
       S(t), as a percent, after t months was found to be given by the function
              S(t) = 78 – 15 log(t + 1)
 What was the average score when the students initially took the
test?
 What was the average score after 4 months?   after 24 months?
12.   Express  log 2x as a sum of logarithms.
13.  Express    as a product.
14.  Express      as a difference of logarithms.
FOR  #15  AND #16,  EXPRESS IN TERMS OF SUMS AND DIFFERENCES
OF LOGARITHMS.
15 
16. 
FOR  #17  AND #18,  EXPRESS AS A SINGLE LOGARITHM, AND IF POSSIBLE, SIMPLIFY.

17.   ln 44 – ln 4
18.   

FOR #19 AND #20, LET  ,  , AND , FIND EACH OF THE FOLLOWING: