A closed cylinder has volume 2156cm3. What will be the radius of its base so that its total surface area is minimum?

Explanation

Let the radius and height of the cylinder be `r` and `h`.


`V=pir^2h`


`2156=pir^2h`


`thereforeV=2156/{pir^2}`

Total surface area`=S=(2pir^2+2pirh)`

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