Question

What is the principal value of cosec^–1(2).

Options

• `pi/6`

• `pi/4`

• `pi/2`

• `pi`

Answer 1

`pi/6`

Explanation:

Let cosec^–1(2) = y

⇒ cosec y = 2 = cosec `(pi/6)`

Range of the principal value of cosec^–1x is `[- pi/2, pi/2] - |0|`

Thus the principal value of cosec^–1(2) is `pi/6`.