What is the maximum volume of a cone that can be carved out of a solid hemisphere of radius?

Find the maximum volume of a cone that can be carved out of a solid hemisphere of radius r cm. 

For the volume of cone to be largest, h = r cm
Volume of the cone 

`1/3pir^2h` 

`=1/3pixxr^2xxr` 

`=1/3pir^3`  

Concept: Surface Area of a Sphere

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