A closed cylinder has volume `2156c m^3dot` What will be the radius of its base so that its total surface area is minimum?

Explanation

Given,

volume of cylinder `v=2156`

`v=pi r^2 ~h`

`therefore h=(2156)/(pi r^2)`

surface area of cylinder,

`s=2 pi r^2+2 pi rh`

`s=2 pi r^2+2 pi r(2156)/(pi r^2)`

`s=2 pi r+2 times (2156)/(r)`

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