How do I evaluate a double integral with a trigonometric function?

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Homework Help Overview

The discussion revolves around evaluating a double integral involving a trigonometric function, specifically the integral of y² sin(xy) with respect to x and y. The original poster is tasked with sketching the region of integration and reversing the order of integration.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • The original poster attempts to determine the limits of integration and expresses confusion regarding the evaluation of the integral, particularly questioning the applicability of integration by parts. Other participants raise concerns about the accuracy of the limits based on the graphical representation of the region.

Discussion Status

The discussion is ongoing, with participants providing feedback on the setup of the integral and the limits of integration. There is an acknowledgment of potential errors in the original poster's approach, but no consensus has been reached on how to proceed with the evaluation of the integral.

Contextual Notes

There is a mention of an attachment related to the integral that is pending approval, which may contain crucial information for the problem context. Additionally, some participants express frustration over the approval process for attachments.

math_04
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Homework Statement



Given the integral shown (in attachment), make a sketch of the region of integration, express the integral with the order of integration reversed and evaluate the integral after reversing the order of integration

Homework Equations





The Attempt at a Solution



So i got the limits as y<= x <= 1 and 0 <= y <= 1

But for the function y^2 sin xy dxdy, how should i integrate that. Integration by parts would not work because v= 0 so the whole integral becomes 0. Should i just read it off the table of integrals. if i do that, the integral becomes -y^2cosxy dx rite?

Thanks
 

Attachments

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oh no, attachment pending approval. not again haha.
 
As said before, if you want quick replies, just host it on imageshack.us or some other image-hosting web service.
 
hahahaha~~~~~~~~

but why do they need to be approved?
 
You seem to have done the same thing you did with the previous problem: your "inner" integral goes from x to 1 while the shaded area in your picture is below the line y= x.
 
ohhh my god ur rite hallsofIvy thanks.

Alright, so the limits change but how do u evaluate that integral. Cant do it by parts cause of the reasons i mentioned.
 

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