Same chapter3 marksDifficulty: Medium
Find the maximum and minimum values of f(x) = x3 − 6x2 + 9x + 5.
Applications of Derivatives
3 marksDifficulty: Medium
The radius of a circle is increasing at 3 cm per second. Find the rate at which its area is increasing when the radius is 10 cm.
Original Khojo Papers practice question — not from a past board paper.
Answer
60π cm2 per second
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
A = πr2, so dA/dt = 2πr(dr/dt) = 2π × 10 × 3 = 60π.
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