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a rancher will use 600m of fencing to build a corral in the shape of a semicircle ont op of a rectangle. find the dimensions that maximize the area of the corral

User Pgiitu
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The dimensions that maximize the area of the corral are 187.5π meters and 112.5π meters.

The perimeter of the corral is 600m, so we have the equation

2r + 2w = 600

where r is the radius of the semicircle and w is the width of the rectangle.

The area of the corral is given by:

A = (1/2)πr² + rw

We want to maximize this area, so we can use optimization techniques. Let's solve the first equation for r:

r = 300 - w

Substituting this into the second equation, we get:

A = (1/2)π(300 - w)² + w(300 - w)

Expanding this equation, we get:

A = 45000 - 450πw - 2w²

To find the maximum value of A, we can take the derivative of A with respect to w and set it equal to zero:

A'(w) = -450π - 4w = 0

Solving for w, we get:

w = 112.5π

Substituting this value of w back into the equation for r, we get:

r = 187.5π

User Hakkar
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