Find the total surface area of a cone whose radius is r/2 and slant height is 2l

1 answer:

3 0

Total surface area of cone: πrl + πr²

Assuming the bottom of the cone is closed.

r = r/2, l = 2l

Total surface Area = π*(r/2)*2l + π(r/2)² = πrl + πr²/4

Total Surface Area = πrl + πr²/4

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