The volume of the solid obtained by rotating the region enclosed by: y=12x-4x^2 and y=0
about the y-axis can be computed using the method of cylindrical shells via an integral V=?

Question

amistre64 · Answer

shells span out from the axis of rotation

amistre64 · Answer

y=0 is the xaxis

amistre64 · Answer

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anonymous · Answer

ok so i am getting the formula as V= 2pi(4x^3-x^4)dx from 0 to 3

amistre64 · Answer

as long as 3 is the zero for it, then yes :)

anonymous · Answer

what do you mean?

amistre64 · Answer

.... which part?  youll have to be more specific

anonymous · Answer

you said the 3 needs to be the 0 for it

amistre64 · Answer

12x-4x^2 = 0, when x = 3

amistre64 · Answer

$$2\pi\int_{0}^{3}12x-4x^2\ dx$$

anonymous · Answer

take the antiderivative from there?