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!

Optimization of 2 eqns

  1. Oct 26, 2011 #1
    1. The problem statement, all variables and given/known data
    I need to optimise a couple of equations.
    I want maximum S for minimum x.

    Constants:
    h, t

    Variables:
    w, j


    2. Relevant equations
    S = ( (j) / (j + 0.5*w) )^2 [Eqn 1]
    x = (const) * (j / w) [Eqn 2]
    [See attachment]

    3. The attempt at a solution
    Well...
    I've tried to re-arrange [Eqn 1] to make j the subject but I cannot. I get:
    ((j)^2) * ( 1 - S + ((S*w)/j) ) = (S*(w^2))/4

    I thought that if I rearrange both equations for j or w and set them equal to each other then I can try to find the min/max of the equation (for the other variable).

    Any ideas/help please?

    thanks


    **Edit Oops... posted in the wrong forum sub category. This is not homework nor coursework. This is a personal project. Either way, I could do with some help :-)
     

    Attached Files:

    Last edited: Oct 26, 2011
  2. jcsd
  3. Oct 26, 2011 #2
    I'm thinking... is it even possible?

    Surely, I can plot S and x over a range of h and w and find where S is maximum and r is minimum??
     
  4. Oct 26, 2011 #3

    hotvette

    User Avatar
    Homework Helper

    Might be instructive to go through some mental gyrations. For example, assume j is a fixed positive number and figure out what value of w will minimize x or maximize S. Then assume j is a fixed negative number and figure out what value of w will minimize x or maximize S. You should be able to zero in rather quickly on what you are looking for.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Optimization of 2 eqns
Loading...