Same chapter3 marksDifficulty: Medium
Use differentials to find the approximate value of √36.6.
Applications of Derivatives
3 marksDifficulty: Medium
Find the intervals in which f(x) = x3 − 3x is increasing and decreasing.
Original Khojo Papers practice question — not from a past board paper.
Answer
It is increasing for x < −1 and for x > 1, and decreasing for −1 < x < 1.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
f′(x) = 3x2 − 3 = 3(x − 1)(x + 1), which is positive outside [−1, 1] and negative inside it.
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