Review question

# Can we find the inverse of a function in three parts? Add to your resource collection Remove from your resource collection Add notes to this resource View your notes for this resource

Ref: R8028

## Suggestion

The function $f$ has domain $\{x: -3< x <3, x \text{ is real}\}$ and is defined by \begin{align*} f:x\to -5-x, \qquad &(-3< x \le -1) \\ f: x\to 2x^3, \qquad&(-1< x \le 1) \\ f:x\to 5-x, \qquad &(1< x <3). \end{align*}

State the range of the function and sketch the graph of $y=f(x)$. Define the inverse relation in similar form and determine whether this inverse relation is a function.

A relation is a set of pairs of values, where the order matters, for example, {(1,4), (2,8), (3,12)}.

You can see that this relation could be associated with the function $f(x) = 4x$.

Can you give an example of a relation which cannot be associated with a function like this?

What is the property of a relation that makes it a function? Can you tell if the inverse you found for this question has this property?