Functions

Pre-Test with Solutions

 

Please select a single answer for each question and record it

 

Correct answers are highlighted in yellow with green font   7 or more correct would be an acceptable score. 

 

  1. A relationship between two sets of real numbers includes the following information:

 

{ (2,3),  (3,3),  (4,2),  (-1,5),  (3,4), (0,1), (1,2)}

 

Is this relationship a function?   a)  Yes   b) No  3 is mapped to both 3 and 4 which violates the definition

 

  1. A mapping between two sets of real numbers is graphed with the results shown below:

Is this the graph of a function?    a) Yes   b) No

 

  1.    A mapping between two sets of real numbers is graphed with the results shown below:

 

 

 

 

Is this the graph of a function?  a) Yes   b) No

 

  For Problems 4-7 assume that f  is a function defined by   f(x) = x|x| +  3x + 5

 

  1. What is  f(-2) ?

 

a)  -2   b)  -5    c)  5    d)  0

 

  1. What is  f(f(0)) ?

a)       0              b)   5    c)  15     d)  45

 

  1. What is  f(3x)?

 

a)  3x|x| +  3x + 15    b)  x|x| +  3x + 5        c)    9x|x| +  9x + 5  d)  9 

 

  1. What is  f(z) ?

a)   z            b) 5+ z|z| +  3z    c)  0          d) not possible

 

 

 

For Problems 8-9  assume  that   f(x) = x3 + 1

 

  1. What is  f(x + h) ?

a) x3 + h + 1            b)  (x+h)3 + 1        c)  x3 + h3 + 1     d) x3 + h3 + 2

 

9)      What is  f(f(-1))?

a)   1       b)   -1      c)   2     d)  0

 

10.  What is the inverse of the function   f(x) = 3x + 1?

 

a)   1/(3x+1)     b)   y/3 + 1/3      c) y/3 – 1/3  or      d)   x/3 – 1/3