Posted by Nevin on .
A cylindrical container with a volume of 3000 cm^3 is constructed from two types of material. The side and bottom of the container cost $0.10/cm^2 and the top of the container costs $0.20/cm^2.
a) Determine the radius and height that will minimize the cost.
b) Determine the ratio of diameter to height.
Could you please help me with these questions please and thank you

Calculus  Optimization 
bobpursley,
Cost=.10*(pi*r^2+2Pi*r*h)+.20PIr^2
volume= PIr^2h or h= volume/PIr^2
h=3000/(PIr^2)
Put that into the cost function for h.
Then take the derivative of cost with respect to r (dCost/dr), set equal to zero, solve for r. 
Calculus  Optimization 
jame,
lol i need help on the same one