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JPHamlett
01-18-2012, 04:26 AM
1: A farmer is trying set up a rectangle fence with a line in the middle like http://intramission.webs.com/Untitled.png



He only has 200 ft of fence, how can he optimize the area


This is as far as I have gotten

http://intramission.webs.com/Untitled-1.jpg


I need help after this part.....

pyroryan
01-18-2012, 04:46 AM
Answer attached.

bg5
01-19-2012, 02:02 AM
3x + 2y = 200
1,5x + y -100 = 0
y = 100 - 1,5x

A = x(100-1,5x)

-1,5x^2 +100x = 0

Peak of parabola func A(x) is in point [p,q]

{ p = -b/2a }

p = -100/-3 = 33,3(3) == x for max A

so:
y = 100 - 1,5x = 100 - 1,5*33,3(3) =~ 50

PatDuffy
01-19-2012, 02:07 AM
Oh boy, I just had a test on optimization problems last month, I already forgot how to do them...

I actually have a test tomorrow on Integrals and Summation, both of which I find easier than optimization was.

Texy
01-23-2012, 03:28 PM
Honesty I found Optimization and Related Rates hard at first (didn't pay attention in class), but now I'm like psshh that's easy stuff.

Jenitt
02-14-2012, 05:01 PM
Math is a really complicated subject to me. This post will help me out for sure! Thanks!.... :)