miinhmiinh9999
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the surface area of a cylinder is increasing by 2 pi square inches per hour and the height is decreasing by 0.1 inches per hour when the radius is 16 inches and the height is 7 inches. how fast is the radius of the cylinder changing?

Respuesta :

The decreasing part area :0.1×2×Pi×r
＝0.2 Pi r
The increasing part is 2 pi square.
the top and bottom area now: 2pi ×(16＋X)
X means the increasing inches.
Then use the top and bottom part miners the decreasing equals to the the increasing part. Then the answer you can calculate by yourself....