Question

3 times the CSA of cone is twice the TSA .then prove that 3r²=h²

Answer 1

Answer:

3r^2=h^2

Step-by-step explanation:

3πrl=2πr(l+r)

3πrl/πr=2l+2r

3l=2l+2r

l=2r

h^2=l^2-r^2

h^2=(2r)^2-r^2

h^2=4r^2-r^2

h^2=3r^2

Answer 2

Step-by-step explanation:

• CSA of a cylinder=
• $2\pi r h$
• TSA of cylinder=
• $2\pi r(r + h)$

$3 \times 2\pi r h = 2\pi r(r + h)$

$3 \times r \times h = r + h$

$3 \times r \times r = h \times h$

$3 {r}^{2} = {h}^{2}$