Question

The curved surface area of frustum of cone is given by

Answer 1

Since a cone is the limiting case of a pyramid, therefore the lateral surfaceof the frustum of a cone can be deduced from the slant surface of thefrustum of a pyramid, i.e. the curved(lateral) surface of the frustum of thecone. l , being the slant height of thefrustum, and being the two radii of bases.

Answer 2

Answer:

it is given by

π(r + R)l

where

r = radius of upper base

l = slant height

R = radius of lower base