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## Homework Statement

Find the volume V of the solid obtained by rotating the region bounded by the given curves about the specified line.

y = 5x, y = 5[itex]\sqrt{x}[/itex] about y = 5

## Homework Equations

A(x)=∏(R

^{2}-r

^{2})

## The Attempt at a Solution

A(x)=∏(5x)

^{2}-(5[itex]\sqrt{x}[/itex])

^{2})

A(x)=∏(25 x

^{2}- [itex]\frac{10}{3}[/itex]x

^{[itex]\frac{3}{2}[/itex]})

V=∏[itex]\int[/itex][itex]^{1}_{0}[/itex](25x

^{2}- [itex]\frac{10}{3}[/itex]x

^{[itex]\frac{3}{2}[/itex]})dx

V=∏([itex]\frac{25}{3}[/itex]x

^{3}-[itex]\frac{4}{3}[/itex]x

^{[itex]\frac{5}{2}[/itex]}) {0,1}

V=∏([itex]\frac{25}{3}[/itex]-[itex]\frac{4}{3}[/itex])

V= [itex]\frac{21}{3}[/itex]∏

Where did I go wrong? I can't figure out the about y=5. If I am correct, you would usually subtract 5 from the two radii, but since they intersect at y=5, the just flip on that intersection point and thus we don't need to find the lost area. Bad explanation, I know, maybe someone can explain it to me.

Thanks in advance!