Answer: 0.
- A 0
- B π/2
- C π
- D 1
Correct answer: A. 0
Explanation: cos 0 = 1, so cos⁻¹(1) = 0.
The graph of sin⁻¹x is confined to a narrow domain [-1,1] (since sine itself only takes values in that range) and range [-π/2,π/2] (the principal value branch chosen to make sine one-one and invertible there).
Concept context
Restricting trig functions to make them invertible, the principal value branches of sin-inverse, cos-inverse, tan-inverse, and friends, and the key identities relating them.