Question

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

Answer 1

given
slant height = 2l
radius = r/2

total surface area of the cone = 2π*radius(radius+slant height)
=2π*r/2[r/2+2l]
=πr{r+4l}/2 sq units

Answer 2

Step-by-step explanation:

Total surface area of cone=πr(r+l)

Given, radius = r/2 and slant height 2l

therefore new total surface area of cone

= π r/2 ( r/2 + 2l )

= π ( r^2/4 + rl )

= πr ( l + r/4 )