a farmer has 2400 feet of fence for a ractangular field along a straght river. no fence is neeeded along the reiver. using calculus find the dimensions of the field which has the largest area

Question

directrix · Answer

Let x be the width of the rectangular field. The perimeter of 3 sides of the field (river side not included) = 2400 - x -x = 2400 - 2x.

Area = x (2400 - 2x)

A(x) = 2400x - 2 x^2

A' (x) = 2400 - 4x

2400 - 4x = 0

x = 600

Dimensions: 600 by 1200

anonymous · Answer

is the answer 600 * 1200

directrix · Answer

|dw:1329973759348:dw|The question is to "find the dimensions."

In the case of a rectangle, that would be one dimension by the other. It would not the the product which the * symbol indicates.

Let's leave it at width: 600 and length: 1200