Question

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

Answer 1

heya mate by using the formula pi*r(r+l)
u can solve this
hope this helps u

Answer 2

R=2r
l=1/2
Total surface area= pie r l +pie r2
22/7×2r×1/2+22/7×4r2
=22/7(r+4r2)
=22/7×r(1+4r)