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Find the domain of definition of f(x) = cos–1(x2–4). |
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Answer» Domain of cos-1x lies in the interval [-1, 1]. Therefore, the domain of cos–1(x2 – 4) lies in the interval [–1, 1]. -1 ≤ x2 - 4 ≤ 1 3 ≤ x2 ≤ 5 ±√3 ≤ x ≤ ± √5 -√5 ≤ x ≤ - √3 and √3 ≤ x ≤ √5 Domain of cos-1(x2 - 4) is [-√5, -√3] ⋃ [√3, √5]. |
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