Match the List-I with List-II
| List-I | List-II | ||
| Function | Range of the principal value branch | ||
| (A) | \( \cos^{-1}x \) | (I) | \( \left(-\displaystyle\frac{\pi}{2},\displaystyle\frac{\pi}{2}\right) \) |
| (B) | \( \mathrm{cosec}^{-1}x \) | (II) | \( (0,\pi) \) |
| (C) | \( \tan^{-1}x \) | (III) | \( [0,\pi] \) |
| (D) | \( \cot^{-1}x \) | (IV) | \( \left[-\displaystyle\frac{\pi}{2},\displaystyle\frac{\pi}{2}\right]-\{0\} \) |
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → (A) - (III), (B) - (IV), (C) - (I), (D) - (II)
(A) \( \cos^{-1}x \)
This matches (III) \( [0,\pi] \).
The domain is [−1, 1]; both end values 0 (at x = 1) and π (at x = −1) are attained.
(B) \( \mathrm{cosec}^{-1}x \)
This matches (IV) \( \left[-\frac{\pi}{2},\frac{\pi}{2}\right]-\{0\} \).
cosec y is undefined at y = 0, so 0 is removed from the range of sin−1.
(C) \( \tan^{-1}x \)
This matches (I) \( \left(-\frac{\pi}{2},\frac{\pi}{2}\right) \).
tan y is undefined at \( \pm\frac{\pi}{2} \), so the end points are excluded.
(D) \( \cot^{-1}x \)
This matches (II) \( (0,\pi) \).
cot y is undefined at 0 and π, so the end points are excluded.
So the matching is (A)-(III), (B)-(IV), (C)-(I), (D)-(II).
Tip: The “co” functions cos−1 and cot−1 take values in [0, π] (open for cot−1); sin−1 and tan−1 take values around 0 in [−π/2, π/2] (open for tan−1).
NCERT (2026-27 edition):
Basic Concepts
