The volume of the solid obtained by rotating the region bounded by $y = x^2,$ and $y = 3 x$ about the line $x = 3$ can be computed using either the washer method or the method of cylindrical shells. Answer the following questions.

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Using the washer method, set up the integral.

with $a =$ and $b =$

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Using the method of cylindrical shells, set up the integral.

with $c =$ and $d =$

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Choose either integral to find the volume.

Volume =

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