The function $f(x)=\cot^{-1}\sqrt{(x+3)x}+\cos^{-1}(\sqrt{x^2+3x+1})$ is defined on the set S, where S is equal to
Answer & explanation
Correct answer: option 4
For the two components to be meaningful $(x +3)x ≥ 0$ and $0≤x^2+3x+1≤1$
Hence $(x + 3)x = 0 ⇒ x = 0, − 3$