Determining double integral limits

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Homework Help Overview

The discussion revolves around evaluating a surface integral over a specified plane defined by the equation \(x^{2}+y^{2}=16\). Participants are attempting to determine the appropriate limits for double integration projected onto the xz-plane.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants express confusion regarding the integration limits and the nature of the surface described by the equation. There is a focus on understanding the projection onto the xz-plane and the implications of the surface being a circular cylinder rather than a plane.

Discussion Status

The discussion is ongoing, with participants questioning the validity of the problem setup and the absence of height information for the cylinder. Some are seeking clarification on the terms used in the problem statement.

Contextual Notes

There is uncertainty regarding the definition of the region R and how it relates to the projection on the xz-plane. Additionally, the lack of specified height for the cylinder is noted as a potential issue in interpreting the problem.

JasonHathaway
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Homework Statement



Evaluate [itex]\iint\limits_S \vec{A} . \vec{n} ds[/itex] over the plane [itex]x^{2}+y^{2}=16[/itex], where [itex]\vec{A}=z\vec{i}+x\vec{j}-3y^{2}\vec{k}[/itex] and S is a part from the plane and R was projected over xz-plane.

Homework Equations



Surface Integral and Double Integration.

The Attempt at a Solution



This is an answered problem, but I didn't get how to determine the integration limits

I understand that I have to integrate with respect to x and z due the fact the region is projected over "xz-plane", and I've to get the limits from the plane equation.

The limits integration in the solution are [itex]\int_0^5 \int_0^4 dz dx[/itex]
 
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JasonHathaway said:

Homework Statement



Evaluate [itex]\iint\limits_S \vec{A} . \vec{n} ds[/itex] over the plane [itex]x^{2}+y^{2}=16[/itex], where [itex]\vec{A}=z\vec{i}+x\vec{j}-3y^{2}\vec{k}[/itex] and S is a part from the plane and R was projected over xz-plane.

Homework Equations



Surface Integral and Double Integration.


The Attempt at a Solution



This is an answered problem, but I didn't get how to determine the integration limits

I understand that I have to integrate with respect to x and z due the fact the region is projected over "xz-plane", and I've to get the limits from the plane equation.

The limits integration in the solution are [itex]\int_0^5 \int_0^4 dz dx[/itex]

##x^2+y^2=16## is not a plane. It's a circular cylinder standing on the xy plane. And you haven't told us how high it goes in the z direction. Draw a picture to see what its projection on the xz plane would look like.
 
And that's what confusing me, there's no height. So the problem is wrong, isn't?
 
I can't make sense of the problem statement. What is R? Is this quoted word for word?
 

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