Answer:
Q(x) is a polynomial, so it is continuous at every number in its domain.
Step-by-step explanation:
All polynomial functions are continuous everywhere.
Continuity at a Point.
Let f be defined on an open interval containing c. We say that f is continuous at c if
lim (x→c) f(x) = f(c)
This indicates three things:
1. The function is defined at x = c.
2. The limit exists at x = c.
3. The limit at x = c needs to be exactly the value of the function at x = c
For the example,
lim (x→c) f(x) = f(c) = 3*(c) − 9*(c)³ − 9