Volume of a solid bound by four surfaces

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Homework Help Overview

The problem involves computing the volume of a solid bounded by four surfaces defined by the equations x+z=1, x+z=−1, z=1−y², and z=y²−1. The subject area relates to multivariable calculus and integration techniques.

Discussion Character

  • Exploratory, Assumption checking, Mathematical reasoning

Approaches and Questions Raised

  • Participants discuss the visualization of the solid and the definition of integration limits. There is an exploration of the order of integration and its impact on the evaluation of the integrals. Questions arise regarding the evaluation of the second integral and potential sign errors.

Discussion Status

The discussion is ongoing, with some participants providing guidance on the order of integrals and questioning the evaluation of zero for the second integral. There is recognition of a mistake made by one participant, but no consensus has been reached on the correct approach yet.

Contextual Notes

Participants are grappling with defining the correct limits and order of integration, which appears to be a central issue in the problem-solving process.

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Homework Statement


Compute the volume of the solid bounded by the four surfaces x+z=1,x+z=−1,z=1−y2,z=y2−1

Homework Equations


Fubini's theorem?

The Attempt at a Solution


I have tried to visualize this solid and define the limits; when I attempted to integrate by dxdzdy (in that order), I set the limits for the first integral as -z-1 to -z+1, the second integral as y^2-1 to 1-y^2, and third integral as -1 to 1, but the I'm not getting a value due to the second integral evaluating as zero.

I feel almost certain that the problem mainly has to do with defining the correct limits and order of integration, but I'm having a bit of trouble here.

Thanks.
 
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How can the second integral be zero? Some sign error?
The order of integrals is useful.
 
Because y2-1=-(1-y^2) and there are no y terms after the first integral, the integral equals 0.
 
If you integrate f(y)=1 from y=-5 to y=5, is the result 0 - or maybe 10?
 
Wow. I can't believe that I made such a dumb mistake. I stared at it for at least 10 min straight.

Thanks for putting up with such a trivial problem. X(
 

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