max/min problem (1 Viewer)

seventhroot

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general steps

> diff it
> set == 0
> solve for x (answer: 15/2)
> test that it is a minimum
 

plutonium-238

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Differentiate the area first and then let it equal to zero and solve for x. After that, sub back into A.
 

integral95

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alternatively, you could use the formula since you're dealing with parabolas :D
 

ConorDevaney

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^ if you asking how you feet from the perimeter and sides equaling zero, you make 60 (the perimeter) equal to the sums of the sides. Therefore 60 = (30 - x) + (30-x) + x +x. Therefore area = x . (30 -x). Therefre area = 30x -x^2
 

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