(−∞,1)(-\infty, 1)(−∞,1)
(8,∞)(8, \infty)(8,∞)
(−∞,1)∪(8,∞)(-\infty, 1) \cup(8, \infty)(−∞,1)∪(8,∞)
(−∞,1)∩(8,∞)(-\infty, 1) \cap(8, \infty)(−∞,1)∩(8,∞)