## Precalculus (6th Edition) Blitzer

$\emptyset$.
Step 1. Rewrite the inequality as $(x-3)^2\lt 0$; we can see that the solution is an empty set $\emptyset$. Step 2. An empty set on a real number line will not show any features except a bare line; thus it will not be provided. Step 3. We can not express an empty set using an interval notation.