Same chapter3 marksDifficulty: Medium
Find the maximum and minimum values of f(x) = x3 − 6x2 + 9x + 5.
Applications of Derivatives
3 marksDifficulty: Medium
Find the minimum value of f(x) = x + 1/x for x > 0.
Original Khojo Papers practice question — not from a past board paper.
Answer
2, at x = 1
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
f′(x) = 1 − 1/x2, which vanishes at x = 1, and f″(x) = 2/x3 is positive there, so it is a minimum, and f(1) = 2.
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