Find Volume of Revolution for y=2+x and y=x^2 about y-axis | Shell Method

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Homework Statement


Find the volume generated by rotating the area bounded by y=2+x and y=x^2 about the y-axis.


Homework Equations


Volume of revolution.

The Attempt at a Solution


shell method
integral (0 to 2) of x(2+x-x^2) dx

I think this can be solved by eliminating the left part and only count the volume of the left side, because the left part of the solid result is covered by the right part. It's a problem in my school because our teacher is debating whether the left part is counted or not.

i'm sorry i can't write in equotion.. I'm newbie
 
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IF the problem really says "rotate around the y-axis, then you are right: the solid is generated is by the region between y= x+ 2 and y= x2 for x> 0. The problem would make more sense and be more interesting if it were rotated around the x-axis.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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