# Calculus

A rectangular field is to be enclosed by a fence and divided into three lots by fences parallel to one of the sides. Find the dimensions of the largest field that can be enclosed with 800 feet of fencing.

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1. 2 * L + 4*w = 800
so
L = 400 - 2w

A = L * w
A = (400 -2w)w
A = -2 w^2 +400 w
dA/dw = 0 at max
= -2 w + 200
w = 100
L = 400 -200 = 200

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2. thanks

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3. hmmm

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