Quiz 5

Problem 1.

A cylindrical can is to be constructed to hold 27 &pgr; cubic inches of liquid. The top and bottom cost $.040 per square inch and the sidews cost $0.10 per sq. inch. Find the dimensions of the can that cost the least in materials.

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Note: CT = $0.40 , CS = $0.10

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The only real answer is the 2nd one

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h is 12

Problem 2

Look at the diagonal of the rectangle. It is a diameter of the circle. Let x and y be the two sides of the retangle. Then

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Problem 3

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Problem 4

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x = 0 is a local max, x = 1 is a local min