1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Maximum/Minimum - hints or pictures?

  1. Mar 16, 2010 #1
    1. The problem statement, all variables and given/known data
    1. A billboard is to made with 100 m2 of printed area, with margins of 2m at the top and bottom, and 4m
    on each side. Find the outside dimensions of the billboard if its total area is to be a minimum.


    2. A cylindrical soft drink can is to have a volume of 500 ml. If the sides and bottom
    are made from aluminum that costs 0.1¢/cm2, while the top is made from a thicker aluminum that costs 0.3
    ¢.cm2. Find the dimensions of the can that minimize its cost.


    3. A farmer raises a bale of hay to a loft 6m above his shoulder by a 20 m rope using a pulley 1.5 m above
    the loft. He walks away from the loft at 1.3 m/s. How fast is the bale rising when it is 2m below the loft?

    What's the third one trying to say?

    2. Relevant equations
    Any pictures or diagrams by any chance?


    3. The attempt at a solution
     
  2. jcsd
  3. Mar 16, 2010 #2
    Have you had a go at this?

    First of all you need to find equations for your problems, and from there differentiate them to find the maximum/minimum.

    If you have a go at the problems, I'll help you some more.
     
  4. Mar 17, 2010 #3
    In #3,

    http://img405.imageshack.us/img405/4035/mmmcopy.png [Broken]

    Is this what it's saying for the diagram?
     
    Last edited by a moderator: May 4, 2017
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook




Loading...
Similar Threads for Maximum Minimum hints Date
Minimum/Maximum problem Mar 15, 2018
Maximum/minimum problem Mar 11, 2018
Maximum-minimum area from a fixed length rope Nov 17, 2017
Local minimum and maximum Nov 14, 2017
Minimum-maximum problem with graph plotting Nov 3, 2017