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MathsMediumMCQ2018 · 15 Apr

Q82.If a right circular cone, having maximum volume, is inscribed in a sphere of radius 3 cm, then the curved surface area (in cm2 ) of this cone is : (1) 8√2π (2) 6√2π (3) 8√3π (4) 6√3π

What This Question Tests

This question involves setting up an optimization problem by relating the dimensions of an inscribed cone to the sphere's radius, finding the maximum volume using differentiation, and then calculating the curved surface area.

Concepts Tested

Maximizing volumeGeometric properties of cone and sphereCurved surface area of a coneDerivatives for optimization

Formulas Used

Volume of cone V = (1/3)πr^2h

Curved surface area of cone CSA = πrl

Relationship between r, h, and R (sphere radius): r^2 = R^2 - (h-R)^2

First derivative test for maxima/minima

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