Determine the set of xxx such that x2−4x+1≤0\frac{x^2-4}{x+1} \leq 0x+1x2−4≤0.
x∈(−∞,−2]∪(−1,2]x \in (-\infty, -2] \cup (-1, 2]x∈(−∞,−2]∪(−1,2]
x∈[−2,−1)∪[2,∞)x \in [-2, -1) \cup [2, \infty)x∈[−2,−1)∪[2,∞)
x∈(−∞,−2]∪[−1,2]x \in (-\infty, -2] \cup [-1, 2]x∈(−∞,−2]∪[−1,2]
x∈[−2,−1]∪[2,∞)x \in [-2, -1] \cup [2, \infty)x∈[−2,−1]∪[2,∞)