So far you have looked at the graphs of relations and their inverses. You will now check how to determine the equation of an inverse given the equation of a function.

Try This 3

1. Use f(x) = 3x − 4 to complete the following table.
   
   

   x	f(x)
   −3
   −2
   −1
   0
   1
   2
   3

2. Use the data from question 1 to help you complete the following table.
   
   

   x	f −1(x)
   	−3
   	−2
   	−1
   	0
   	1
   	2
   	3

3. Determine an equation of the form f −1(x) =_______ that could be used to represent the table of values in question 2.

4. 
   
   1. Complete questions 1 to 3 using the function f(x) = 2x2.
   2. Is the inverse of f(x) = 2x2 a function? Explain.
   3. Is it reasonable to use the notation f −1(x) for question 3?

Save your work in your course folder.

Share 1

With a partner or group, discuss the following questions based on the information from Try This 3.

1. How did your equations for question 3 compare?
2. How could you have determined the equation in question 3 without making a table of values?
3. Why is it difficult to write the inverse of 2x2 using function notation? Is it possible to use function notation for this inverse?

If required, save a record of your discussion in your course folder.