Question

the total surface area of a cone whose radius is pi/2 and slant hight is 2l is?​

Answer 1

Answer:

$\text{ the total surface area of cone} \\ =πr(r+l). 2r and \: slant \: \: height \\ =2l. 2r(2r+2l) \\ =π( 4r2+rl) \\ = πr (l+4r ).$

Answer 2

Answer:

We know, the total surface area of cone=πr(r+l). 2r and slant height =2l. 2r(2r+2l) =π( 4r2+rl) = πr (l+4r ).