Same chapter3 marksDifficulty: Medium
Use differentials to find the approximate value of √36.6.
Applications of Derivatives
3 marksDifficulty: Medium
Find the maximum and minimum values of f(x) = x3 − 6x2 + 9x + 5.
Original Khojo Papers practice question — not from a past board paper.
Answer
A local maximum of 9 at x = 1 and a local minimum of 5 at x = 3.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
f′(x) = 3x2 − 12x + 9 = 3(x − 1)(x − 3), and f″(x) = 6x − 12 is negative at x = 1 and positive at x = 3.
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