Finding Volume of Solid Bounded by Paraboloid and Planes

Krayfish
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Homework Statement


Find the volume of the solid enclosed by the paraboloid z=x^2 + 3y^2 and the planes x=0, y=x, y=1, z=0

Homework Equations


I'm not really sure what's getting me about this, but I'm not really sure how to proceed after finding the x, y, and z intercepts...

The Attempt at a Solution


x intercept: 0
y intercept: 0
z intercept: 0

Would I just take bounds of y to be 1 and x and the bounds of x to be 0 and 1?
∫∫x^2 + 3y^2 dydx → The dy result would be yx^2 + y^3 → (x^3+x^3 -(x^2+1)) → 2X^3 - x^2 - 1 and then continue to integrate... ∫2x^3-x^2-1 dx → ((x^4)/2 -(x^2)/3 -x) → 1/2 - 1/3 - 1 = -5/6?

If that correct or am I missing something important?
 
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Krayfish said:

Homework Statement


Find the volume of the solid enclosed by the paraboloid z=x^2 + 3y^2 and the planes x=0, y=x, y=1, z=0

Homework Equations


I'm not really sure what's getting me about this, but I'm not really sure how to proceed after finding the x, y, and z intercepts...

The Attempt at a Solution


x intercept: 0
y intercept: 0
z intercept: 0

Would I just take bounds of y to be 1 and x and the bounds of x to be 0 and 1?
∫∫x^2 + 3y^2 dydx → The dy result would be yx^2 + y^3 → (x^3+x^3 -(x^2+1)) → 2X^3 - x^2 - 1 and then continue to integrate... ∫2x^3-x^2-1 dx → ((x^4)/2 -(x^2)/3 -x) → 1/2 - 1/3 - 1 = -5/6?

If that correct or am I missing something important?
Have you drawn a sketch of the solid whose volume you're supposed to find? Also, you should draw a sketch of the region in the x-y plane that forms the base of this solid. That would help you figure out what the integration limits need to be.
 
Mark44 said:
Have you drawn a sketch of the solid whose volume you're supposed to find? Also, you should draw a sketch of the region in the x-y plane that forms the base of this solid. That would help you figure out what the integration limits need to be.
I struggled to sketch it myself so I ended up using a software and plotted the parabaloid with the two y= planes. I'm not really sure where to go from there, all the examples we've done thus far have had at least 1 non zero intercept.
 
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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