## burhan101 2 years ago [check my work ] A cylindrical container, with a volume of 4000cm³ is being constructed to build candies. The cost of the base and lid is \$0.005/cm², and the cost of the side walls is \$0.0025/cm². Determine the dimensions of the cheapest possible container. Okay so I finished the problem and got the right radius but i'm having problems finding the height !

1. burhan101

2. dan815

whys ur handwriting so neat..

3. dan815

its hard to read that scan tho

4. dan815

lets just go over the steps

5. dan815

tell me what you wrote for your surface area equation and volume equation

6. dan815

|dw:1371786843467:dw|

7. dan815

minizmine cost*

8. dan815

either way u do same functioon lol

9. dan815

is this what u did?

10. dan815

u can rewrite h as a function of r or r as a function of h and substitute into 2nd equation and take the derivative solve for the critical points, and see what dimensions minimize cost

11. burhan101

ill post a better picture cause i have the whole question finished

12. burhan101

just that last step is missing

13. burhan101

@dan815

14. saloniiigupta95

I don't know what the above discussion is going into, but if you have found out the radius, just substitute the value in pi*r^2*h = 4000 since the volume of cylinder is given by pi*r^2*h...

15. dan815

yes looks right

16. dan815

i checked ur first few steps its right upto there

17. burhan101

mhm but then i have to find h

18. burhan101

i'm not gettingg the right value for h

19. saloniiigupta95

@ dan815 |dw:1371790110621:dw| It should be 2 times- one for lid and one for base...