Question
Mathematics Question on Inverse Trigonometric Functions
sin\left\\{2\,cos^{-1}\left(- \frac{3}{5}\right)\right\\} is equal to
A
256
B
2524
C
54
D
−2524
Answer
−2524
Explanation
Solution
sin\left\\{2\,cos^{-1}\left(- \frac{3}{5}\right)\right\\} = 2\,sin\left\\{cos^{-1}\left(- \frac{3}{5}\right)\right\\}cos\left\\{cos^{-1}\left(- \frac{3}{5}\right)\right\\} = 2\,sin\left\\{\pi - cos^{-1} \frac{3}{5}\right\\}\times \left(-\frac{3}{5}\right) = -\frac{6}{5}sin\left\\{cos^{-1} \frac{3}{5}\right\\} =−56sin(sin−11−259) =−56×54=−2524