The price drop of a product in rupees over x months follows P(x) = 100 cos⁻¹(x−1). The practical domain for x (in months) is:

The price drop of a product in rupees over x months follows P(x) = 100 cos⁻¹(x−1). The practical domain for x (in months) is:

• A. [-1, 1]
• B. [0, 2]
• C. [1, 3]
• D. [0, ∞)

Answer: B) [0, 2]

Explanation: The domain of cos⁻¹(y) is [-1, 1]. So −1 ≤ x − 1 ≤ 1, which gives 0 ≤ x ≤ 2.