Warm Up Solutions

Name the domain and range of $R^{- 1}$ .

$R = \{(- 2, - 6), (- 1, - 3), (0, 0), (1, 3), (2, 6)\}$

$R^{- 1} domain : \{- 6, - 3, 0, 3, 6\} range : \{- 2, - 1, 0, 1, 2\}$

Use the relation to write a function rule $f (x)$ , and its inverse $f^{- 1} (x)$ .

$f (x) = 3 x f^{- 1} (x) = \frac{1}{3} x$

Note

Recall that a function rule is another way to say “write the equation that represents the ordered pairs.” This equation is a linear equation, but not all functions are linear.

Asking yourself questions like this can help you find the function rule:
Q: How are the y-values changing in R? The x-values?

A: The y-values are increasing by 3, and the x-values are increasing by 1.