Question

the total surface area of a cone whose radius is R/2 slant height is 2L
1. 2πr(L+R)
2. πr(L+r/2
3. πr(L+R)
4. 2πrL​

Answer 1

Answer:

Total surface area of cone=πr(r+l)

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

Therefore new total surface area of cone =π

2r ( 2r+2l)

=π( 4r 2+rl)

=πr(l+4r )

Answer 2

Answer:

The total surface area of a cone whose radius is R/2 slant height is 2L

Therefore new total surface area of cone =π

2r (2r+2L)

=π (4r2+rL)

=πr (L+4r)

hope it's help.