Question Detail
Question
A cylinder's radius increases at 2 cm/sec, height decreases at 3 cm/sec. Rate of change of volume when both are 10 cm?
Correct Answer
Option A is the correct answer.
Detailed Explanation
( V = \pi r^2 h \implies \dot{V} = \pi(2rh\dot{r} + r^2\dot{h}) ). Given ( r=10, h=10, \dot{r}=2, \dot{h}=-3 ). ( \dot{V} = \pi(2(10)(10)(2) + 100(-3)) = \pi(400 - 300) = 100\pi ).
Hint
Differentiate the volume formula using the product rule.