Answer:
Damian's mistake was to have included number 3 in the domain
Step-by-step explanation:
Observing the graph
we know that
The domain of the graph is the interval
(-∞,3) U (3,∞)
All real numbers less than 3 and greater than 3
The number 3 is not included in the domain (open circle in the graph)
therefore
Damian's mistake was to have included number 3 in the domain
