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# Volumes of Rotation y-axis Watch

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1. Find the volume of the solid generated when rotating the closed region between the curves y=8(x)^1/2 and y=x^2 fully about the y-axis

this what i've got so far...

y/8 = x^1/2
y^2/64 = x
x^2 = y^4/4096

their intersection is x=4, y=16

V= pi[y^5/5 - 4096y^2/2] with 4 at t and 0 at bottom of bracket
2. (Original post by Custardcream000)
Find the volume of the solid generated when rotating the closed region between the curves y=8(x)^1/2 and y=x^2 fully about the y-axis

this what i've got so far...

y/8 = x^1/2
y^2/64 = x
x^2 = y^4/4096

their intersection is x=4, y=16

V= pi[y^5/5 - 4096y^2/2] with 4 at t and 0 at bottom of bracket
In your evaluation, you seem to be using x-values as your limits, despite the fact that you are rotating about the y axis.
Furthermore, there seems to have been some confusion, at present the left hand side of your equality should read .

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Updated: October 7, 2016
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