Target Exam

CUET

Subject

Section B1

Chapter

Inverse Trigonometric Functions

Question:

Which of the following is the range of the principal value of $\sec ^{-1} x$.

Options:

$\left(-\frac{\pi}{2}, \frac{\pi}{2}\right)$

$\left(0, \frac{\pi}{2}\right)$

$[0, \pi)$

$[0, \pi]-\left\{\frac{\pi}{2}\right\}$

Correct Answer:

$[0, \pi]-\left\{\frac{\pi}{2}\right\}$

Explanation:

The correct answer is Option (4) - $[0, \pi]-\left\{\frac{\pi}{2}\right\}$

$y=\sec^{-1}x.$

$\text{Principal value range of } \sec^{-1}x \text{ is defined so that sec }y \text{ is one–one}.$

$y\in[0,\pi],\;y\ne\frac{\pi}{2}.$

$\text{Correct option: }[0,\pi]-\left\{\frac{\pi}{2}\right\}.$