Answer:
x base radius = 3.169 cm
h height of cylinder = 6.34
Step-by-step explanation:
We have
V cylinder = V = 200 cc
We wll fnd frst the areas involve
Let x = radius of base then area of the base = π*x² and this is the area of the top too
For lateral area we need to get h the height of the clinder as fuction of x
V = πx²h ⇒ h= v/πx² ⇒ h = 200/πx²
Now the total area of the cylinder is:
A(x) = Area of the base + area of the top + lateral area
A(x) = 2*π*x² + 2πx h ⇒ A(x) = 2*π*x² + 2πx (V/πx² )
A(x) = 2*π*x² + 400/x
Taking derivatives:
A´(x) = 4πx - 400/x²
A´(x) = 0 4πx - 400/x² =0 ⇒ πx - 100/x² = 0
( πx³ - 100 )/ x² = 0 πx³ - 100 = 0 x³ = 100/3.14 x = 3.169 cm
and h = 200/πx² ⇒ h = 6.34 cm