Problem: Find the domain of the function f(x)=[∣x2−x−2∣]1.
Solution
Solution: x must not satisfy 0≤x2−x−2<1⇒x must not satisfy x2−x−2=(x−2)(x+1)≥0⇔x∈(−∞,−1]∪[2,+∞) AND must not satisfy x2−x−2≤1⇔x2−x−3<0⇔x∈(21−13,21+13). Thus, x∈(−∞,21−13]∪(−1,2)∪[21+13,+∞).
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Source: MathNet,
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