What is the domain of f(x)=1x2−9f(x) = \frac{1}{\sqrt{x^2-9}}f(x)=x2−91?
(−3,3)(-3, 3)(−3,3)
(−∞,−3]∪[3,∞)(-\infty, -3] \cup [3, \infty)(−∞,−3]∪[3,∞)
(−∞,−3)∪(3,∞)(-\infty, -3) \cup (3, \infty)(−∞,−3)∪(3,∞)