Results 1 to 7 of 7
Like Tree2Thanks
  • 2 Post By romsek

Thread: exploring behaviour of minimums

  1. #1
    Newbie
    Joined
    Mar 2019
    From
    Oceana
    Posts
    6

    exploring behaviour of minimums

    Hey guys,

    I'm a little stuck again. I'm wondering if someone would be able to point me in the general direction of how to complete this question??

    Please see image below:
    exploring behaviour of minimums-problem-2.jpg

    Thankyou so much!
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor
    Joined
    Nov 2013
    From
    California
    Posts
    6,463
    Thanks
    2820

    Re: exploring behaviour of minimums

    It's basically the same as the last one.

    Width is 2m.
    Length is variable but given once n is chosen
    instead of height you are given volume. calculate the height from the volume as before.
    height becomes a function of $n$

    Then a single strap length is $4+2h$ (I assume there is no strap lengthwise anymore)

    You've got $n$ of these so $L=n(4+2h(n))$

    Proceed on from there.
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Newbie
    Joined
    Mar 2019
    From
    Oceana
    Posts
    6

    Re: exploring behaviour of minimums

    Hi romsek,

    once again I'm a little confused as that seems to be different to both of the resources I have (I may be wrong though.) Are either of these correct?
    exploring behaviour of minimums-working-1.jpg
    exploring behaviour of minimums-working-2.jpg
    Follow Math Help Forum on Facebook and Google+

  4. #4
    MHF Contributor
    Joined
    Nov 2013
    From
    California
    Posts
    6,463
    Thanks
    2820

    Re: exploring behaviour of minimums

    Quote Originally Posted by ifailedmaths View Post
    Hi romsek,

    once again I'm a little confused as that seems to be different to both of the resources I have (I may be wrong though.) Are either of these correct?
    Click image for larger version. 

Name:	working 1.jpg 
Views:	4 
Size:	70.2 KB 
ID:	39282
    Click image for larger version. 

Name:	working 2.jpg 
Views:	3 
Size:	84.3 KB 
ID:	39283
    oh I see, the length can be variable. I read it as a multiple of 1.5.

    I'll take another look.
    Follow Math Help Forum on Facebook and Google+

  5. #5
    Newbie
    Joined
    Mar 2019
    From
    Oceana
    Posts
    6

    Re: exploring behaviour of minimums

    Quote Originally Posted by romsek View Post
    oh I see, the length can be variable. I read it as a multiple of 1.5.

    I'll take another look.
    thankyou, that'd be much appreciated.
    Follow Math Help Forum on Facebook and Google+

  6. #6
    MHF Contributor
    Joined
    Nov 2013
    From
    California
    Posts
    6,463
    Thanks
    2820

    Re: exploring behaviour of minimums

    Quote Originally Posted by ifailedmaths View Post
    thankyou, that'd be much appreciated.
    $n=2$

    $\dfrac 3 2 \leq x < 3$

    $V = 2 x h$

    $\ell = 2(2\cdot 2 + 2 h) = 8+4 h = 8 + \dfrac{4V}{2x} = 8 + \dfrac{2V}{x}$

    $n=3$ is very similar and I'm sure you can figure it out.

    I don't know what they mean by optimization. Are you supposed to select a length $x$ for a chosen $n$ such that $\ell$ is minimized?
    Thanks from ifailedmaths and topsquark
    Follow Math Help Forum on Facebook and Google+

  7. #7
    Newbie
    Joined
    Mar 2019
    From
    Oceana
    Posts
    6

    Re: exploring behaviour of minimums

    Quote Originally Posted by romsek View Post
    $n=2$

    $\dfrac 3 2 \leq x < 3$

    $V = 2 x h$

    $\ell = 2(2\cdot 2 + 2 h) = 8+4 h = 8 + \dfrac{4V}{2x} = 8 + \dfrac{2V}{x}$

    $n=3$ is very similar and I'm sure you can figure it out.

    I don't know what they mean by optimization. Are you supposed to select a length $x$ for a chosen $n$ such that $\ell$ is minimized?
    Thankyou for explaining! And yes, I think so.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Infimum and minimums
    Posted in the Calculus Forum
    Replies: 6
    Last Post: Feb 8th 2009, 06:50 PM
  2. Exploring fast growing functions - help with research
    Posted in the Discrete Math Forum
    Replies: 0
    Last Post: Jan 15th 2009, 08:52 AM
  3. Replies: 2
    Last Post: Mar 25th 2008, 07:38 AM
  4. minimums
    Posted in the Calculus Forum
    Replies: 1
    Last Post: Jan 17th 2008, 04:13 PM

/mathhelpforum @mathhelpforum