MathematicsMedium66×since 2002Q4116Let SSS be the set of all solutions of the equation cos−1(2x)−2cos−1(1−x2)=π,x∈[−12,12]\cos ^{-1}(2 x)-2 \cos ^{-1}\left(\sqrt{1-x^{2}}\right)=\pi, x \in\left[-\frac{1}{2}, \frac{1}{2}\right]cos−1(2x)−2cos−1(1−x2)=π,x∈[−21,21]. Then \sum_\limits{x \in S} 2 \sin ^{-1}\left(x^{2}-1\right) is equal to :Aπ−2sin−1(34)\pi-2 \sin ^{-1}\left(\frac{\sqrt{3}}{4}\right)π−2sin−1(43)Bπ−sin−1(34)\pi-\sin ^{-1}\left(\frac{\sqrt{3}}{4}\right)π−sin−1(43)C−2π3\frac{-2 \pi}{3}3−2πDNoneCheck answerSkip