Find volume between parabloid and parabolic sylinder

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Homework Help Overview

The problem involves finding the volume of a region bounded by the surfaces defined by the equations x = y² + z² and x = 2 - y². The subject area pertains to calculus, specifically triple integrals and volume calculations in three-dimensional space.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants discuss the setup of the integral and the limits of integration. There is mention of using cylindrical coordinates and the challenges associated with the surfaces being of different types (one being a surface of revolution).

Discussion Status

The discussion is ongoing, with participants exploring different interpretations of the problem statement and clarifying the equations involved. Some guidance has been offered regarding the setup of the integral, but there is no explicit consensus on the final approach yet.

Contextual Notes

There is uncertainty regarding the correct interpretation of the problem statement, particularly the meaning of "and" in the context of the equations provided. Participants are also addressing potential typographical errors in the original post.

MeMoses
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EDIT - well its too late to change the title now, but I can spell corectly... sometimes.

Homework Statement


Find the volume of the region bounded by x = y**2 and z**2 and x = 2 - y**2

Homework Equations


Triple integrals and cylindricals

The Attempt at a Solution


I started by roughly graphing the two figures and I got stuck here for some reason. I tried cylindricals, but I figured there would be a better way. For whatever reason I can't get my head around the limits of integration for this problem. Solving the integral once I have it shouldn't be a problem, but I just need to setup the integral that's why my work here is limited. Thanks for any help
 
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Hi MeMoses! :smile:
MeMoses said:
EDIT - well its too late to change the title now, but I can spell corectly... sometimes.

I think you meant a diabolic sylinder! :biggrin:
I tried cylindricals, but I figured there would be a better way. For whatever reason I can't get my head around the limits of integration for this problem. Solving the integral once I have it shouldn't be a problem, but I just need to setup the integral that's why my work here is limited.

One surface is of revolution, but the other isn't, so there's no short-cuts here. :redface:

You'll have to take slices of width dx perpendicular to the x-axis, and then slice those slices either "horizontally" (with width dz) or "vertically" (with width dy), and double-integrate :wink:
 
tiny-tim said:
Hi MeMoses! :smile:I think you meant a diabolic sylinder! :biggrin:One surface is of revolution, but the other isn't, so there's no short-cuts here. :redface:

You'll have to take slices of width dx perpendicular to the x-axis, and then slice those slices either "horizontally" (with width dz) or "vertically" (with width dy), and double-integrate :wink:
The real question is...
What's a Sylinder?
 
MeMoses said:
EDIT - well its too late to change the title now, but I can spell corectly... sometimes.

Homework Statement


Find the volume of the region bounded by x = y**2 and z**2 and x = 2 - y**2

What does the red highlighted definition mean? There isn't an equation after the word "and".
 
LCKurtz said:
What does the red highlighted definition mean? There isn't an equation after the word "and".

Hi LCKurtz! :smile:

"and" means "+" :wink:
 
tiny-tim said:
Hi LCKurtz! :smile:

"and" means "+" :wink:

How do you know he doesn't mean ##x = y^2## and ##x = z^2##?
 
the title? :rolleyes:
 
tiny-tim said:
Hi LCKurtz! :smile:

"and" means "+" :wink:

LCKurtz said:
How do you know he doesn't mean ##x = y^2## and ##x = z^2##?

tiny-tim said:
the title? :rolleyes:

Well, given that he obviously didn't post the problem word for word, I wouldn't make the assumption that the title is correct. Perhaps the problem is actually stated as I propose and the OP thinks that makes a paraboloid. No way of knowing until we see the correct wording one way or the other.
 
My bad, its x = y**2 + z**2 as thought
 
  • #10
Would the limits
y**2+z**2 < x < 2-y**2,
-sqrt(1-(z**2)/2) < y <sqrt(1-(z**2)/2),
-sqrt(2) < z < sqrt(2)
get the correct volume?
 
  • #11
MeMoses said:
Would the limits
y**2+z**2 < x < 2-y**2,
-sqrt(1-(z**2)/2) < y <sqrt(1-(z**2)/2),
-sqrt(2) < z < sqrt(2)
get the correct volume?

Yes, those are correct.
 

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